PROCESS FOR REMOVING MALODORS FROM MODIFIED POLYAMINES

Abstract: Methods for deodorizing polyamines useful as laundry detergent adjuncts, especially as cotton soil release agents, are described. The methods involve contacting the polyamines with water at a temperature higher than the boiling point of water, contacting the polyamines with a non-condensable gas, and mixtures thereof.

Description: PROCESS FOR REMOVING MALODORS FROM MODIFIED POLYAMINES FIELD OF THE INVENTION The present invention relates to processes for removing malodorous compounds from modified polyamines The purified polyamines are suitable for use 10 in laundry compositions especially compositions comprising low or nil perfume CROSS REFERENCE This Application claims priority under Title 35, United States Code 1 19(e) from Provisional Application Serial Number 60/020,104, filed June 19, 1996 BACKGROUND OF THE INVENTION 15 Chemical manufacturers have long dealt with the fact that organic chemical reactions proceed, in general, with the formation of undesired by-products These undesirable by-products, although only a small percentage of the total material present, can impact the final product in substantial ways, for example, by providing unwanted color or odor It has therefore become an integral part of manufacturing 20 processes to provide for the removal of these unwanted by-products In the field of laundry detergents, formulators must consider the aesthetics of the final products as well as the efficacy For this reason and others, odor free starting materials are highly desirable For example, perfumes are optionally added to detergent formulations to impart a desirable fragrance, but some consumers desire 25 a "fragrance free" material The presence of malodorous materials in laundry starting materials limits the usefulness of these materials in fragrance sensitive formulations The removal of undesirable malodors from laundry detergent ingredients has been a focus of research for many years. Odorless surfactants are routinely produced and formulated into laundry products. Recently, a new class of materials, namely, the 30 modified polyamines, have found increasing use in laundry detergent compositions The unique set of properties ascribed to these modified polyamines makes them a desirable addition to a wide range of laundry compositions including granular and liquid detergent compositions, dryer-added fabric softeners and fabric pre¬ conditioning compositions 35 These modified polyamines have as their starting materials in many cases polyalkyleneimine backbones Many forms of polyalkylenearrunes have been known to those skilled in the laundry art and are obtainable in low odor forms However, recent discoveries reveal that modifications of these polyalkyleneamines produce a class of materials having unique surface active and fabric substantive properties as well as novel metal chelation properties. During the modification of these polyamine backbones, many chemical reagents, especially ethylene oxide in the presence of a base catalyst, are used which can result in volatile, highly reactive by-products which are in themselves malodorous or are malodor precursors. Normal purification means are too costly or inefficient to produce modified polyamines having sufficiently low odor profiles. Water extraction is inefficient since many of the polyamines are highly water soluble and absorb large quantities of water. It has now been surprisingly found that these modified polyamines can have their malodorous compounds removed by several direct methods. One method includes contacting the modified polyamine with up to one weight equivalent of water at a temperature above the boiling point of water under certain temperature and pressure conditions. Normally heating of polyamines is avoided due to the propensity of these compounds to thermally degrade and produce malodors and color bodies However, by skillfully employing the process of the present invention, the modified polyamines are efficiently deodorized while the integrity of the product composition is maintained. In addition, several methods have been developed for removal of malodor when anhydrous conditions must prevail such as the case of quaternized polyamine backbones or when a hydrolyzable functionality is contained within the polyamine It is an object of the present invention to provide a process for removal of malodorous compounds from the polyamines described herein below This process involves contacting the polyamine with water under conditions that do not degrade the final product or which change the properties of the purified material. It is a further object of the present invention to provide a method of removing malodorous materials from polyamines at any step during the polyamine chemical modification process. BACKGROUND ART US. Patent 4,726,909 Otten et al., issued February 23, 1988 describes low odor polyoxyalkylene polyether polyol compositions. U.S. Patent 5,241,092 discloses a process for deodorizing edible fats and oils SUMMARY OF THE INVENTION The present invention relates to a process for removing malodors from modified polyamines comprising the step of contacting a modified polyamine with water at a temperature above the boiling point of water It is also an object of the present invention to provide a process for removing malodors from modified polyamines by treating the polyamine with a non- condensable gas It is a further object of the present invention to provide a process for removing malodors from modified polyamines by treating the polyamine with a combination of water and a non-condensable gas. All percentages, ratios and proportions herein are by weight, unless otherwise specified All temperatures are in degrees Celsius (° C) All documents cited are, in relevant part, incorporated herein by reference DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for removing undesirable malodorous compounds that are present as a result of the preparation of modified polyamines. Typically the deodorization process is conducted after all chemical modifications have been made to the polyamines. However, this process may be conducted at any point in the preparation of the modified polyamines especially in cases where a malodorous material is also a chemically reactive species that will further react to adulterate the bulk material if allowed to remain during the final processing steps. For example, the formulator may identify a particular step that produces the bulk of malodorous materials and removal of these malodorous materials at this stage may be advantageous Modified polyamines The modified polyamines produced by the present process (having utility for example as cotton soil release polymers) which can develop malodors components during preparation are described herein below. The processes described in the present invention work equally well for all embodiments of the modified polyamines These modified polyamines comprise backbones that can be either linear or cyclic The polyamine backbones can also comprise polyamine branching chains to a greater or lesser degree. In general, the polyamine backbones described herein are modified in such a manner that each nitrogen of the polyamine chain is thereafter described in terms of a unit that is substituted, quaternized, oxidized, or combinations thereof For the purposes of the present invention the term "modification" is defined as replacing a backbone -NH hydrogen atom by an E unit (substitution), quaternizing a backbone nitrogen (quaternized) or oxidizing a backbone nitrogen to the N-oxide (oxidized) The terms "modification" and "substitution" are used interchangeably when referring to the process of replacing a hydrogen atom attached to a backbone nitrogen with an E unit Quaternization or oxidation may take place in some circumstances without substitution, but preferably substitution is accompanied by oxidation or quaternization of at least one backbone nitrogen The linear or non-cyclic polyamine backbones that are desirable as cotton soil release agents prepared by the present invention have the general formula H | [HaN-RJn+j-rN-RJm-tN-RJn-NHz said backbones prior to subsequent modification, comprise primary, secondary and tertiary amine nitrogens connected by R "linking" units The cyclic polyamine backbones that are desirable as cotton soil release agents prepared by the present invention have the general formula H | R [H 2 N-R]n-k+r-[N-R] m -[N-R]n-[N-R]k-NH 2 said backbones prior to subsequent modification, comprise primary, secondary and tertiary amine nitrogens connected by R "linking" units Primary amine nitrogens comprising the backbone or branching chain once modified are defined as V or Z "terminal" units For example, when a primary amine moiety, located at the end of the main polyamine backbone or branching chain having the structure H 2 N-R]- is modified, it is thereafter defined as a V "terminal" unit, or simply a V unit However, some or all of the primary amine moieties can remain unmodified subject to the restrictions further described herein below These unmodified primary amine moieties by virtue of their position in the backbone chain remain "terminal" units Likewise, when a primary amine moiety, located at the end of the main polyamine backbone having the structure -NH 2 is modified, it is thereafter defined as a Z "terminal" unit, or simply a Z unit This unit can remain unmodified subject to the restrictions further described herein below In a similar manner, secondary amine nitrogens comprising the backbone or branching chain once modified are defined as W "backbone" units For example, when a secondary amine moiety, the major constituent of the backbones and branching chains of the compounds prepared by the present invention, having the structure H — [N-R]- is modified, it is thereafter defined as a W "backbone" unit, or simply a W unit. However, some or all of the secondary amine moieties can remain unmodified. These unmodified secondary amine moieties by virtue of their position in the backbone chain remain "backbone" units. In a further similar manner, tertiary amine nitrogens comprising the backbone or branching chain once modified are further referred to as Y "branching" units. For example, when a tertiary amine moiety, which is a chain branch point of either the polyamine backbone or other branching chains or rings, having the structure —[N-R]— is modified, it is thereafter defined as a Y "branching" unit, or simply a Y unit. However, some or all or the tertiary amine moieties can remain unmodified. These unmodified tertiary amine moieties by virtue of their position in the backbone chain remain "branching" units. The R units associated with the V, W and Y unit nitrogens which serve to connect the polyamine nitrogens, are described herein below. The final modified structure of the polyamines prepared by the present invention can therefore be represented by the general formula V(n-M)W m YnZ for linear polyamine cotton soil release polymers and by the general formula V (n _ k+ i)W m Y n Y' k Z for cyclic polyamine cotton soil release polymers. For the case of polyamines comprising rings, a Y" unit of the formula I R —[N-R]— serves as a branch point for a backbone or branch ring. For every Y' unit there is a Y unit having the formula —[N-R]- that will form the connection point of the ring to the main polymer chain or branch. In the unique case where the backbone is a complete ring, the polyamine backbone has the formula [H 2 N-R] n -[N-R] m -[N-R]n— therefore comprising no Z terminal unit and having the formula V n -kW m YnY'k wherein k is the number of ring forming branching units. Preferably the polyamine backbones comprise no rings. In the case of non-cyclic polyamines, the ratio of the index n to the index m relates to the relative degree of branching. A fully non-branched linear modified polyamine according to the present invention has the formula VW m Z that is, n is equal to 0. The greater the value of n (the lower the ratio of m to n), the greater the degree of branching in the molecule. Typically the value for m ranges from a minimum value of 4 to about 400, however larger values of m, especially when the value of the index n is very low or nearly 0, are also preferred. Each polyamine nitrogen whether primary, secondary or tertiary, once modified, is further defined as being a member of one of three general classes; simple substituted, quaternized or oxidized. Those polyamine nitrogen units not modified are classed into V, W, Y, or Z units depending on whether they are primary, secondary or tertiary nitrogens. That is unmodified primary amine nitrogens are V or Z units, unmodified secondary amine nitrogens are W units and unmodified tertiary amine nitrogens are Y units for the purposes of the present invention. Modified primary amine moieties are defined as V "terminal" units having one of three forms: a) simple substituted units having the structure: E— N-R — I E b) quaternized units having the structure: E-N-R — I E wherein X is a suitable counter ion providing charge balance, and c) oxidized units having the structure Modified secondary amine moieties are defined as W "backbone" units having one of three forms a) simple substituted units having the structure -N-R— E b) quaternized units having the structure —N-R — I E wherein X is a suitable counter ion providing charge balance, and c) oxidized units having the structure Modified tertiary amine moieties are defined as Y "branching" units having one of three forms a) unmodified units having the structure — N-R— b) quaternized units having the structure wherein X is a suitable counter ion providing charge balance, and c) oxidized units having the structure Certain modified primary amine moieties are defined as Z "terminal" units having one of three forms: a) simple substituted units having the structure -N I -E E b) quaternized units having the structure. wherein X is a suitable counter ion providing charge balance; and c) oxidized units having the structure. When any position on a nitrogen is unsubstituted or unmodified, it is understood that hydrogen will substitute for E. For example, a primary amine unit comprising one E unit in the form of a hydroxyethyl moiety is a V terminal unit having the formula (HOCH 2 CH 2 )HN- For the purposes of the present invention there are two types of chain terminating units, the V and Z units The Z "terminal" unit derives from a terminal primary amino moiety of the structure -NH 2 Non-cyclic polyamine backbones comprise only one Z unit whereas cyclic polyamines can comprise no Z units The Z "terminal" unit can be substituted with any of the E units described further herein below, except when the Z unit is modified to form an N-oxide. In the case where the Z unit nitrogen is oxidized to an N-oxide, the nitrogen must be modified and therefore E cannot be a hydrogen. The polyamines prepared by the present invention comprise backbone R "linking" units that serve to connect the nitrogen atoms of the backbone. R units comprise units that are referred to as "hydrocarbyl R" units and "oxy R" units. The "hydrocarbyl" R units are C 2 -Cι 2 alkylene, C_j;-Cι 2 alkenylene, C3-C j 2 hydroxyalkylene wherein the hydroxyl moiety may take any position on the R unit chain except the carbon atoms directly connected to the polyamine backbone nitrogens; C4-Cι 2 dihydroxyalkylene wherein the hydroxyl moieties may occupy any two of the carbon atoms of the R unit chain except those carbon atoms directly connected to the polyamine backbone nitrogens; Cg-Cι 2 dialkylarylene which for the purpose of the present invention are arylene moieties having two alkyl substituent groups as part of the linking chain. For example, a dialkylarylene unit has the formula although the unit need not be 1,4-substituted, but can also be 1,2 or 1,3 substituted C 2 -Ci2 alkylene, preferably ethylene, 1,2-propylene, and mixtures thereof, more preferably ethylene. The "oxy" R units comprise -(R 1 O) x R 5 (OR 1 ) x -, -CH 2 CH(OR 2 )CH 2 O) z - (R 1 O) y R 1 (OCH2CH(OR 2 )CH 2 ) w -, -CH 2 CH(OR 2 )CH 2 -, -(R^R 1 -, and mixtures thereof. Preferred R units are C 2 -C ι 2 alkylene, C3 -C 1 2 hydroxyalkylene, C4-C 12 dihydroxyalkylene, C 8 -Cι 2 dialkylarylene, -(R^R 1 -, -CH 2 CH(OR 2 )CH 2 - ( -(CH 2 CH(OH)CH 2 O) z (R l O) y R l (OCH 2 CH-(OH)CH 2 ) w -, -(R l O) x R 5 (OR ] ) x -, more preferred R units are C 2 -Cι 2 alkylene, C3-Cι 2 hydroxy-alkylene, C4-Cι 2 dihydroxyalkylene, -(CH 2 CH(OH)CH 2 O) z - (R 1 O) y R 1 (OCH 2 CH-(OH)CH 2 ) w -, and mixtures thereof, even more preferred R units are C 2 -C ι 2 alkylene, C3 hydroxyalkylene, and mixtures thereof, most preferred are C 2 -C6 alkylene. The most preferred backbones comprise at least 50% R units that are ethylene. Rl units are C 2 -C6 alkylene, and mixtures thereof, preferably ethylene R 2 is hydrogen, and -(R Ϊ Q^B, preferably hydrogen. R 3 is Cj-C i g alkyl, C7-C j 2 arylalkylene, C7-C12 alkyl substituted aryl, Cg- C j 2 aryl, and mixtures thereof , preferably C ι -Cι 2 alkyl, Cj-C 12 arylalkylene, more preferably C ι-Cι 2 alkyl, most preferably methyl R 3 units serve as part of E units described herein below R 4 is Cι -Cι 2 alkylene, C4-Cι 2 alkenylene, Cg-C ι 2 arylalkylene, Cg-Cio arylene, preferably C i-C 10 alkylene, Cg-Cι 2 arylalkylene, more preferably C 2 -Cg alkylene, most preferably ethylene or butylene. R 5 is Cι-Cι 2 alkylene, C3-Cι 2 hydroxyalkylene, C4-Cι 2 dihydroxyalkylene, Cg-C 12 dialkylarylene, -C(O)-, -C(O)NHR 6 NHC(O)-, -C(O)(R 4 ) r C(O)-, -R 1 (OR 1 )-, -CH 2 CH(OH)CH 2 O(R 10)yR 1 OCH 2 CH(OH)CH 2 -, -CH 2 CH(OH)CH 2 -, R 5 is preferably ethylene, -C(O)-, -C(O)NHR 6 NHC(O)-, -R^OR 1 )-, -CH 2 CH(OH)CH 2 -, -CH 2 CH(OH)CH 2 O(R!θ) y RlθCH 2 CH- (OH)CH 2 -, more preferably -CH 2 CH(OH)CH 2 - R^ is C 2 -Cι 2 alkylene or Cg-Cι 2 arylene. The preferred "oxy" R units are further defined in terms of the Rl, R 2 , and R5 units. Preferred "oxy" R units comprise the preferred Rl , R 2 , and R^ units. The preferred compounds prepared by the present processes are cotton soil release agents comprising at least 50% Rl units that are ethylene. Preferred R*, R 2 , and R^ units are combined with the "oxy" R units to yield the preferred "oxy" R units in the following manner. i) Substituting more preferred R 5 into -(CH 2 CH 2 O) x R 5 (OCH 2 CH 2 ) x - yields -(CH 2 CH 2 O) x CH 2 CHOHCH 2 (OCH 2 CH 2 ) x - ii) Substituting preferred R 1 and R 2 into -(CH 2 CH(OR 2 )CH 2 O) z - (R 1 O) y R 1 O(CH 2 CH(OR 2 )CH 2 ) vv - yields -(CH 2 CH(OH)CH 2 O) 2 - (CH 2 CH 2 O)yCH 2 CH 2 O(CH2CH(OH)CH 2 ) w -. iii) Substituting preferred R 2 into -CH 2 CH(OR 2 )CH 2 - yields -CH 2 CH(OH)CH 2 - E units are selected from the group consisting of hydrogen, Cι-C 22 alkyl, C 3 -C 22 alkenyl, C 7 -C 22 arylalkyl, C 2 -C 22 hydroxyalkyl, -(CH 2 ) p CO 2 M, - (CH 2 ) q SO 3 M, -CH(CH 2 CO 2 M)CO 2 M, -(CH 2 ) p PO 3 M, -(R 1 ©)^, -C(O)R 3 , preferably hydrogen, C 2 -C 22 hydroxyalkylene, benzyl, Cι -C 22 alkylene, -(R 1 O) m B, -C(O)R 3 , -(CH 2 ) p CO 2 M, -(CH 2 ) q SO 3 M, -CH(CH 2 CO 2 M)CO 2 M, more preferably C l-C 22 alkylene, -(R^^B, -C(O)R 3 , -(CH 2 ) p CO 2 M, -(CH 2 ) q SO 3 M, 1 1 -CH(CH 2 CO 2 M)CO 2 M, most preferably C !-C 2 2 alkylene, -(Rlθ) x B, and -C(O)R 3 When no modification or substitution is made on a nitrogen then hydrogen atom will remain as the moiety representing E E units do not comprise hydrogen atom when the V, W or Z units are 5 oxidized, that is the nitrogens are N-oxides. For example, the backbone chain or branching chains do not comprise units of the following structure ? T T — N— R or H— N— R or — N~ H I I I H H H Additionally, E units do not comprise carbonyl moieties directly bonded to a 0 nitrogen atom when the V, W or Z units are oxidized, that is, the nitrogens are N- oxides. The E unit -C(O)R 3 moiety is not bonded to an N-oxide modified nitrogen, that is, there are no N-oxide amides having the structure 5 or combinations thereof B is hydrogen, Cι-C 6 alkyl, -(CH 2 ) q SO 3 M, -(CH 2 ) p CO 2 M, -(CH 2 ) q - (CHSO 3 M)CH 2 SO 3 M, -(CH 2 ) q (CHSO 2 M)CH 2 SO 3 M, -(CH 2 ) p PO 3 M, -PO 3 M, preferably hydrogen, -(CH 2 ) q SO 3 M, -(CH 2 ) q (CHSO3M)CH 2 SO 3 M, -(CH 2 ) q - (CHSO 2 M)CH 2 SO 3 M, more preferably hydrogen or -(CH 2 ) q SO 3 M 0 M is hydrogen or a water soluble cation in sufficient amount to satisfy charge balance. For example, a sodium cation equally satisfies -(CH 2 ) p CO 2 M, and -(CH 2 ) q SO3M, thereby resulting in -(CH 2 ) p CO 2 Na, and -(CH 2 ) q SO3Na moieties More than one monovalent cation, (sodium, potassium, etc.) can be combined to satisfy the required chemical charge balance. However, more than one anionic group 5 may be charge balanced by a divalent cation, or more than one mono-valent cation may be necessary to satisfy the charge requirements of a poly-anionic radical For example, a -(CH 2 )pPO3M moiety substituted with sodium atoms has the formula - (CH 2 ) p PO3Na3. Divalent cations such as calcium (Ca 2+ ) or magnesium (Mg 2+ ) may be substituted for or combined with other suitable mono-valent water soluble 0 cations. Preferred cations are sodium and potassium, more preferred is sodium 12 X is a water soluble anion such as chloπne (Cl"), bromine (Br) and iodine (I " ) or X can be any negatively charged radical such as sulfate (SO4 2 ") and methosulfate (CH3SO3-) The formula indices have the following values p has the value from 1 to 6, q has the value from 0 to 6, r has the value 0 or 1, w has the value 0 or 1, x has the value from 1 to 100, y has the value from 0 to 100, z has the value 0 or 1, k is less than or equal to the value of n, m has the value from 4 to about 400, n has the value from 0 to about 200, m + n has the value of at least 5 Malodor Removal Procedure A Water Vaporization The present invention relates to a process for removing the malodorous compounds from modified polyamines such as those described hereinbefore by the use of up to one weight equivalent of liquid water which is converted m situ to steam This process can be operated in a continuous, semi-continuous or batchwise manner When the water is introduced in a particular way and/or in a particular form, the removal of undesirable volatile impurities in the modified polyamine is also found to be improved The level of impurities in the starting modified polyamine, however, may dictate the operating conditions of the deodoπzation process Severe operating conditions, for example, may be necessary as the impurities level in the starting mateπal increases in the case of a continuous or semi-continuous process The amount of water that is used in the present process is typically less than one weight equivalent of the polyamine, preferably less than 0 5 weight equivalent For example, 500 gm of water is normally sufficient to deodoπze 1000 gm of polyamine However, the polyamines of the present invention are highly water soluble materials and the formulator may select a final product that is not void of all deodoπzation water and therefore more than the theoretical amount of water can be used in processes of this type In the simplest case, the modified malodorous polyamine in the form of a solid, gel, viscous syrup, or liquid, is charged to a vessel The vessel may be open to the atmosphere but typically is a closed system adapted for gas sparging, vacuum, pressuπzation, and other typical processing aids compatible with the deodoπzation of modified polyamines Although the present water vapoπzation process provides some degree of agitation, the formulator may find it advantageous to provide an external source of mechanical agitation This is especially true for lower temperature processes or for processes that involve highly water absorbing modified polyamines After the malodor-containing substrate is charged to the deodoπzation vessel, a source of heat is used to increase the temperature of the modified polyamine to greater than the boiling point of water For the purposes of the present invention the term "above the boiling point of water" is taken to be the temperature at which injected liquid water is vaporized to steam In addition, the temperature must be sufficiently high whereby the vaporization of injected water does not sufficiently cool the surrounding heat transfer media (typically the modified polyamine being deodorized) in a manner sufficient to interrupt the deodorization rate or cause a change in the rate of incoming water The observed boiling point of water at standard atmospheric conditions is taken to be 100° C. However, processes conducted at higher altitudes or under reduced pressure will obviously have an adjusted "boiling point of water" Heating can be accomplished by jacketing the vessel, by immersion of either steam or electrical heating coils, or by any other means wherein the temperature can be suitably controlled It is necessary that uniform dispersion of the heat takes place to insure that the material is maintained at a steady temperature Once the desired temperature is achieved, water is introduced at such a rate that the liquid water is completely vaporized to steam by the surrounding medium. This water, now in the form of steam, serves to extract the volatile malodor compounds as it passes out of the solution The rate at which the liquid water is introduced into the vessel must not cool the polyamine to such a degree that there is an accumulation of liquid water Alternatively, a pre-determined amount of water may be added to a vessel containing the polyamine to be deodorized. The vessel may be at room temperature or at any temperature below the boiling point of water The vessel is then heated to a temperature above the boiling point of water The formulator may choose to remove all of the water present or the formulator may choose to leave any water still present beyond the amount necessary to deodorize the polyamine For example, 0 5 weight equivalent of water may be necessary to remove the malodorous materials from a sample of polyamine yet the formulator may add an excess of 0 5 weight equivalents of water After removing 0.5 weight equivalents of water, the now deodorized polyamine contains 0 5 weight equivalents of water This water may be desirable for the subsequent formulation of the polyamine or may be necessary for further processing steps Therefore the process of the present invention does not require removal of all added water from the polyamine. Both the quantity of heat and water introducing means employed, however, may not be critical as long as the starting material in the deodorization vessel is subject to a particular amount of a water at a deodorization temperature of at least about 1 10° C to about 200° C, preferably from about 135° C to about 175° C, more preferably from about 140° C to about 160° C when the temperature is measure at standard atmospheπc conditions The initial temperature at which the deodoπzation process is conducted may be higher or lower than the final deodoπzation temperature One preferable embodiment of the present invention increases the temperature of the modified polyamine to the minimum temperature sufficient to conduct deodoπzation and then over the course of the process increases the temperature stepwise or at a steady rate until a final deodonzation temperature is obtained This steady increase in temperature or "temperature ramping" is conducted at a rate of from about 0 01° C per minute to about 10° C per minute, preferably from about 0 1° C per mmute to about 5° C per minute, more preferably from about 0 1° C per minute to about 1° C per minute Typically a temperature change of approximately 100° C is suitable for deodorizing the polyamines, preferably the temperature change is approximately 60° C over the course of the deodoπzation process It has been surpπsingly found that the residence time in which the introduced water remains in the liquid state pπor to vaporization, is a critical vanable adjustable under the conditions of the present process The liquid phase residence time can be adjusted by the formulator to fit the type of polyamine present or the degree of deodoπzation necessary This ability to adjust the rate of vapoπzation allows for a wide control in the liquid water contact time For example, the formulator may find that a longer liquid water/impuπty contact time favors the removal of a particular malodor This control can accomplished by the adjusting the rate of water introduction as well as by varying the temperature profile of the deodoπzation vessel Unlike the deodonzation process familiar to those skilled in the art of edible fats and oils processing, it is not cπtical to limit the amount of water used in the removal of malodorous materials according to the present process This is especially critical when high temperatures are necessary to remove unwanted malodorous compounds. Unlike the deodorization of edible fats and oils which comprise hydrolyzable triglyceride ester linkages, the process of the present invention makes use of the surprisingly stable nature and water compatibility of the modified polyamines descπbed herein above The water may be introduced at any depth of the reaction vessel especially if sufficient agitation or mixing of the modified polyamine is achieved The formulator may rely upon the agitation caused by the vaporization of the water and escape of the resultant steam to efficiently mix the contents of the deodoπzation vessel The source of water may be introduced at the bottom of the deodoπzation vessel by a single water injection port, along a removable vertical tube having a plurality of water injection ports extending from the bottom of the vessel to a level just below the surface of the polyamine, or by a plurality of water injection ports along the surface of the vessel itself. The shape and means in which the water is introduced into the vessel containing the modified polyamine does not effect the efficiency of the present process. B Gaseous Purge Process The present invention also relates to a process for removing the malodorous compounds from modified polyamines by the use of a particular amount of a non- condensable gas which can be operated in a continuous, semicontinuous or batchwise manner. Examples of non-condensable gases suitable for use in the present process are helium, argon, carbon dioxide, and nitrogen. However, this list is not meant to be totally inclusive of all gases suitable for the present invention. When the non- condensable gas is introduced in a particular way and/or in a particular form, the removal of undesirable volatile impurities in the modified polyamine is also found to be improved. The level of impurities in the starting modified polyamine, however, may dictate the operating conditions of the deodorization process. Severe operating conditions, for example, may be necessary as the impurities level in the starting material fed to the deodorization vessel increases. The stripping gas may be introduced by means such as sparging or distributing means having particular orifice sizes, preferably placed in at least one upper, middle and lower sections of the vessel Both the quantity of heat and stripping gas introducing means employed, however, may not be critical as long as the -starting material in the deodorization vessel is subject to a particular amount of a stripping gas at a deodorization temperature of at least about 1 10° C to about 200° C, preferably from about 135° C to about 175° C, more preferably from about 140° C to about 160° C Typically a temperature change of approximately 100° C is suitable for deodorizing the polyamines, preferably the temperature change is approximately 60° C over the course of the deodorization process. The amount of the non-condensable gas entering the vessel should be at least the minimum necessary to produce a deodorized modified polyamine product having the desired characteristics. The minimum amount of the non-condensable gas may vary depending on the type of deodorization vessel used, the type and extent of modifications made to the polyamine backbone, and with the reaction conditions used to make said modifications The present invention does not limit the volume of gas introduced per unit time nor the amount of gas introduced per unit mass of polyamine nor the volume of gas introduced per unit mass of water C Water Vaporization and Gaseous Purge The water vaporization process may be combined with the gaseous purge process. Typically this combination is employed for reasons of deodorization vessel configuration, susceptibility of the polyamine to degradation by air, or to increase the efficiency of low temperature deodorization. The gaseous purge can commence before or after the introduction of water into the vessel and may also begin or end at any temperature point In addition, vacuum may be used to assist in the deodorization process. The vacuum may be formed by a pump, by a steam injector, or by any other suitable means of forming a vacuum. The amount of vacuum may vary or be constant during the deodorization process. The amount of vacuum present during the deodorization process can range from a slight vacuum to full vacuum For the purposes of the present invention the term "slight vacuum" is defined as a drop in the pressure of the deodorization vessel of 10% or less from the ambient pressure. For the purposes of the present invention the term "full vacuum" is defined as a pressure inside the deodorization vessel of less than 0.1 mm Hg. All other levels of vacuum is equally suitable for use in the present process. A preferred embodiment of the present invention comprises the steps of a) charging a vessel with a modified polyamine in need of deodorization and heating to a temperature above the boiling point of water; b) optionally passing an inert gas through the polyamine while heating to a temperature above the boiling point of water, c) optionally reducing the internal pressure of the vessel containing the polyamine; d) contacting the polyamine with water at a temperature above the boiling point of water; e) optionally removing all of the added water; and f) recovering the deodorized modified polyamine. A similarly preferred embodiment of the present invention comprises the steps of: a) charging a vessel with a malodorous modified polyamine, b) adding up to one weight equivalent of water; and c) heating the solution to a temperature above the boiling point of water, d) optionally removing all of the added water; and e) recovering the deodorized modified polyamine A further preferred method of deodorizing the modified polyamines according to the present invention comprises the steps of a) charging a vessel with a malodorous modified polyamine, b) sparging the polyamine with a non-condensable gas, c) optionally heating the polyamine during sparging, d) subjecting the polyamine to a vacuum; e) optionally heating the polyamine as the polyamine is held under vacuum; and f) recovering the deodorized modified polyamine. A still further method of deodorizing the modified polyamines according to the present invention comprises the steps of: a) contacting a modified polyamine with water below the boiling point of water; and b) sparging the polyamine with a non-condensable gas while the polyamine is above the boiling point of water; c) optionally removing all of the added water from the modified polyamine; and d) recovering the deodorized modified polyamine. Another method of deodorizing the modified polyamines of the present invention comprises the steps of: a) subjecting a modified polyamine to a vacuum; b) heating the polyamine under vacuum to a temperature above the observed boiling point of water; c) introducing water to the polyamine while under vacuum and at a temperature above the observed boiling point of water sufficient to vaporize the water; d) optionally removing all of the added water; and e) recovering the deodorized modified polyamine. A more preferred method of deodorizing the modified polyamines of the present invention comprises the steps of: a) charging a modified polyamine in need of deodorization to a vessel; b) sparging the polyamine with non-condensable gas; c) raising the temperature of the polyamine to a temperature above the boiling point of water while continuing to sparge the polyamine with a non-condensable gas; d) contacting the polyamine with water; e) continuing to raise the temperature of the polyamine while continuing to sparge with a non-condensable gas and continuing to contact the polyamine with water, f) optionally removing ail of the added water; and 18 g) recovering the modified polyamine A similarly more preferred method of deodorizing the modified polyamines of the present invention comprises the steps of: a) charging a modified polyamine in need of deodorization to a vessel, 5 b) sparging the polyamine with non-condensable gas; c) creating a vacuum in the vessel, d) raising the temperature of the polyamine to a temperature above the boiling point of water while continuing to sparge the polyamine with a non-condensable gas under vacuum; 0 e) contacting the polyamine with water under vacuum; and f) continuing to raise the temperature of the polyamine while continuing to sparge with a non-condensable gas and continuing to contact the polyamine with water under vacuum. The process of the present invention is preferably conducted at temperatures 5 that do not increase the amount of unwanted color. In some instances, the deodorization process when conducted at a stage in the preparation of the polyamines prior to the final step, removes reactive intermediates as well as malodorous components and hence serves to prevent the formation of undesired color as well as undesired odors. 0 The following are examples of odor removal by the process of the present invention. EXAMPLE 1 To a 200 mL beaker is charged PEI 1800 E7 (89.9 gm), the preparation of which is described herein below. Water (10.4 gm) is added and the solution is 5 preheated to about 98° C in a microwave oven A thermometer is suspended in the solution and the contents of the beaker is stirred on a hot plate open to the atmosphere with a slow stream of nitrogen gas blowing over the top. The solution is heated to about 160° C over a period of about 30 minutes wherein essentially all of the water is removed. After cooling, the solution is graded by expert panelists and 0 found to have diminished malodor EXAMPLE 2 To a 200 mL beaker is charged PEI 1800 E7 (70.0 gm), the preparation of which is described herein below. Water (30.0 gm) is added and the solution is 5 preheated to about 88° C in a microwave oven A thermometer is suspended in the solution and the contents of the beaker is stirred on a hot plate open to the atmosphere with a slow stream of nitrogen gas blowing over the top The solution is 97/48673 PC1YUS97/10478 19 heated to about 160° C over a period of about 45 minutes wherein essentially all of the water is removed After cooling, the solution is graded by expert panelists and found to have diminished malodor EXAMPLE 3 Preparation of PEI 1800 E2 The ethoxylation is conducted in a 2 gallon stirred stainless steel autoclave equipped for temperature measurement and control, pressure measurement, vacuum and inert gas purging, sampling, and for introduction of ethylene oxide as a liquid A -20 lb net cylinder of ethylene oxide (ARC) is set up to deliver ethylene oxide as a liquid by a pump to the autoclave with the cylinder placed on a scale so that the weight change of the cylinder could be monitored A 750 g portion of polyethyleneimine (PEI) (Nippon Shokubai, Epomin SP- 018 having a listed average molecular weight of 1800 equating to about 0 417 moles of polymer and 17 4 moles of nitrogen functions) is added to the autoclave The autoclave is then sealed and purged of air (by applying vacuum to minus 28" Hg followed by pressurization with nitrogen to 250 psia, then venting to atmospheric pressure) The autoclave contents are heated to 130 °C while applying vacuum After about one hour, the autoclave is charged with nitrogen to about 250 psia while cooling the autoclave to about 105 °C. Ethylene oxide is then added to the autoclave incrementally over time while closely monitoring the autoclave pressure, temperature, and ethylene oxide flow rate The ethylene oxide pump is turned off and cooling is applied to limit any temperature increase resulting from any reaction exotherm The temperature is maintained between 100 and 110 °C while the total pressure is allowed to gradually increase during the course of the reaction After a total of 750 grams of ethylene oxide has been charged to the autoclave (roughly equivalent to one mole ethylene oxide per PEI nitrogen function), the temperature is increased to 1 10 ° C and the autoclave is allowed to stir for an additional hour At this point, vacuum is applied to remove any residual unreacted ethylene oxide Next, vacuum is continuously applied while the autoclave is cooled to about 50 °C while introducing 376 g of a 25% sodium methoxide in methanol solution (1 74 moles, to achieve a 10% catalyst loading based upon PEI nitrogen functions) The methoxide solution is sucked into the autoclave under vacuum and then the autoclave temperature controller setpoint is increased to 130 °C A device is used to monitor the power consumed by the agitator The agitator power is monitored along with the temperature and pressure Agitator power and temperature values gradually increase as methanol is removed from the autoclave and the viscosity of the mixture increases and stabilizes in about 1 hour indicating that most of the methanol has been removed The mixture is further heated and agitated under vacuum for an additional 30 minutes Vacuum is removed and the autoclave is cooled to 105 °C while it is being charged with nitrogen to 250 psia and then vented to ambient pressure The autoclave is charged to 200 psia with nitrogen. Ethylene oxide is again added to the autoclave incrementally as before while closely monitoring the autoclave pressure, temperature, and ethylene oxide flow rate while maintaining the temperature between 100 and 1 10 °C and limiting any temperature increases due to reaction exotherm After the addition of 4500 g of ethylene oxide (resulting in a total of 7 moles of ethylene oxide per mole of PEI nitrogen function) is achieved over several hours, the temperature is increased to 110 °C and the mixture stirred for an additional hour The reaction mixture is then collected in nitrogen purged containers and eventually transferred into a 22 L three neck round bottomed flask equipped with heating and agitation. The strong alkali catalyst is neutralized by adding 167 g methanesulfonic acid (1.74 moles). The reaction mixture is then deodorized by passing about 100 cu ft of inert gas (argon or nitrogen) through a gas dispersion frit and through the reaction mixture while agitating and heating the mixture to 130 °C The final reaction product is cooled slightly and collected in glass containers purged with nitrogen. In other preparations the neutralization and deodorization is accomplished in the reactor before discharging the product

Claims: WHAT IS CLAIMED IS: 1. A process for removing malodors from amines comprising the step of contacting an amine with water at a temperature above the boiling point of water. 2. A process for removing malodors from modified polyamines comprising the step of contacting a modified polyamine said modified polyamine comprising a polyamine backbone corresponding to the formula: H | K-N-Rln+i -[N-R] m -[N-R] n -NH 2 having a modified polyamine formula V( n+ ι )W m Y n Z or a polyamine backbone corresponding to the formula: I H j R [H 2 N-R]n-k+r—[N-R] m -[N-R]n-iN-R] k -NH 2 having a modified polyamine formula wherein k is less than or equal to n, said polyamine backbone prior to modification has a molecular weight greater than about 200 daltons, wherein i) V units are terminal units having the formula: O X ' E-N-R — or E-N-R- or E-N t-R- ii) W units are backbone units having the formula: O ? X - t —N-R— or —N-R— or — N-R— E E E iii) Y units are branching units having the formula: E X " ° — N-R— or —N-R— or — N-R— 1 ' ; and iv) Z units are terminal units having the formula: wherein backbone linking R units are selected from the group consisting of C 2 -C 12 alkylene, C4-C12 alkenylene, C3-C12 hydroxyalkylene, C4-C12 dihydroxy-alkylene, Cg-C } 2 dialkylarylene, -(R 1 O) X R! -, - (R1O) X R5(OR1 ) X -, - (CH2CH(OR 2 )CH 2 O) z (RlO) y R 1 (OCH2CH(OR 2 )CH2)w-, C(O)(R 4 ) r C(O)-, -CH 2 CH(OR 2 )CH 2 -, and mixtures thereof; wherein R 1 is C 2 -C6 alkylene and mixtures thereof; R 2 is hydrogen, -(R^O) x B, and mixtures thereof; R 3 is Cj-Qg alkyl, C7-C12 arylalkyl, C7-C12 alkyl substituted aryl, Cg-Cj^ aryl, and mixtures thereof; R 4 is Cj-Cι 2 alkylene, C4-C12 alkenylene, Cg-Ci2 arylalkylene, C^-C JQ arylene, and mixtures thereof; R^ is Cj-C ι 2 alkylene, C3-C12 hydroxyalkylene, C4-C12 dihydroxy-alkylene, Cg-C 12 dialkylarylene, -C(O)-, -C(O)NHR 6 NHC(O)-, -R^ORl)-, -C(O)(R 4 ) r C(O)-, -CH 2 CH(OH)CH 2 -, -CH 2 CH(OH)CH 2 O- (R 1 O) y R 1 OCH 2 CH(OH)CH2-. and mixtures thereof; R 6 is C 2 -C i2 alkylene or C6-Cι 2 arylene; E units are selected from the group consisting of hydrogen, Cι -C 22 alkyl, C3-C22 alkenyl, C7-C22 arylalkyl, C2-C22 hydroxyalkyl, -(CH 2 ) p CO 2 M, -(CH 2 ) q SO 3 M, -CH(CH 2 CO 2 M)CO 2 M, -(CH 2 ) p P03M, -(R!θ) x B, -C(O)R 3 , and mixtures thereof; provided that when any E unit of a nitrogen is a hydrogen, said nitrogen is not also an N- oxide; B is hydrogen, C j-Cό alkyl, -(CH 2 ) q SO 3 M, -(CH 2 ) p CO 2 M, - (CH 2 ) q -(CHSθ3M)CH 2 SO 3 M, -(CH2) q -(CHSθ2M)CH2SO 3 M, - (CH2) p Pθ3M, -PO3M, and mixtures thereof; M is hydrogen or a water soluble cation in sufficient amount to satisfy charge balance; X is a water soluble anion; m has the value from 4 to about 400; n has the value from 0 to about 200; p has the value from 1 to 6, q has the value from 0 to 6; r has the value of 0 or 1 ; w has the value 0 or 1 ; x has the value from 1 to 100; y has the value from 0 to 100; z has the value 0 or 1 ; with water at a temperature above the boiling point of water. 3. A process according to either Claim 1 or 2 wherein the temperature is from about 1 10° C to about 200° C, preferably from about 135° C to about 175° C, more preferably from about 140° C to about 160° C. 4. A process according to any of Claims 1-3 further comprising the step of stirring the modified polyamine in the presence of a non-condensable gas prior to contacting the modified polyamine with water. 5. A process according to Claim 1 wherein the modified polyamine is contacted with water at a temperature above the boiling point of water and the pressure at which the deodorization process is conducted is less than standard atmospheric pressure. 6. A process for removing malodors from a modified polyamine comprising the steps of: a) charging a vessel with a malodorous modified polyamine and heating to a temperature above the boiling point of water; b) optionally passing an inert gas through the polyamine while heating to a temperature above the boiling point of water; c) optionally reducing the internal pressure of the vessel containing the polyamine; and d) contacting the polyamine with water at a temperature above the boiling point of water. 7. A process according to Claim 6 wherein the internal pressure of the vessel in less than atmospheric pressure. 8. A process according to either of Claims 6 or 7 wherein a non-condensable gas is passed through the polyamine during the step of contacting the polyamine with water, preferably contacting a modified polyamine with a non-condensable gas while increasing the temperature at a rate sufficient to avoid the formation of color, preferably the temperature is increased at a rate of from about 0.01° C per minute to about 1° C per minute. 9. A process for deodorizing a modified polyamine the modified polyamine comprising a polyamine backbone corresponding to the formula: ? I [H 2 N-R]rrf 1 -[N-R] m -[N-R] n -NH 2 having a modified polyamine formula V( n+ ι )W m Y n Z or a polyamine backbone corresponding to the formula: H | R [H 2 N-R] n -k+i— [N-R]m-[N-R] n -[N-R]k-NH 2 having a modified polyamine formula wherein k is less than or equal to n, said polyamine backbone prior to modification has a molecular weight greater than about 200 daltons, wherein i) V units are terminal units having the formula: ii) W units are backbone units having the formula: —N-R — or —N ¥Λ-R — or — ? N-R- I or I ° r I E E E iii) Y units are branching units having the formula: —N-R— or iv) Z units are terminal units having the formula: wherein backbone linking R units are selected from the group consisting of C 2 -C i2 alkylene, C4-C12 alkenylene, C3-C12 hydroxyalkylene, C4-C 12 dihydroxy-alkylene, C8-C12 dialkylarylene, -(R 1 O) X R 1 -, - (RlO) x R5(ORl) x -, - (CH 2 CH(OR 2 )CH 2 O) z (R 1 O) y R J (OCH 2 CH(OR 2 )CH 2 ) w -, C(O)(R 4 ) r C(O)-, -CH 2 CH(OR 2 )CH 2 -, and mixtures thereof; wherein R' is C2-Cg alkylene and mixtures thereof; R 2 is hydrogen, -(R O) x B, and mixtures thereof; R 3 is Ci-Cj g alkyl, C7-C12 arylalkyl, C7-C 12 alkyl substituted aryl, Cg-Ci 2 ^^ ^ mixtures thereof; R 4 is C1-C 12 alkylene, C4-C12 alkenylene, Cg-Cj2 arylalkylene, Cg-Ci Q arylene, and mixtures thereof; R^ is C1-C12 alkylene, C3-C12 hydroxyalkylene, C4-C12 dihydroxy-alkylene, Cg-C{ 2 dialkylarylene, -C(O)-, -C(O)NHR 6 NHC(O)-, -R^OR 1 )-, -C(O)(R 4 ) r C(O)-, -CH 2 CH(OH)CH 2 -, -CH 2 CH(OH)CH 2 O- (R 1 O) y R 1 OCH 2 CH(OH)CH 2 -, and mixtures thereof; R 6 is C 2 -Cι 2 alkylene or C^-C 12 arylene; E units are selected from the group consisting of hydrogen, C1 -C22 alkyl, C3-C22 alkenyl, C7-C22 arylalkyl. C 2 -C 22 hydroxyalkyl, -(CH 2 ) p CO2M, -(CH2) q SO 3 M, -CH(CH 2 CO 2 M)CO2M, -(CH2) p Pθ3M, -(R! O) X B, -C(O)R 3 , and mixtures thereof; provided that when any E unit of a nitrogen is a hydrogen, said nitrogen is not also an N- oxide; B is hydrogen, Cj-Cg alkyl, -(CH2) q SO3M, -(CH2) p CO2M, - (CH 2 )q-(CHSO3M)CH 2 SO3M, -(CH2) q -(CHSO 2 M)CH2SO 3 M, - (CH2)pPO3M, -PO3M, and mixtures thereof; M is hydrogen or a water soluble cation in sufficient amount to satisfy charge balance; X is a water soluble anion; m has the value from 4 to about 400; n has the value from 0 to about 200; p has the value from 1 to 6, q has the value from 0 to 6; r has the value of 0 or 1 ; w has the value 0 or 1 ; x has the value from 1 to 100; y has the value from 0 to 100; z has the value 0 or 1 ; comprising the steps of: a) charging the modified polyamine in need of deodorization to a vessel; b) sparging the polyamine with a non-condensable gas; c) raising the temperature of the polyamine to a temperature above the boiling point of water while continuing to sparge the polyamine with a non-condensable gas; d) contacting the polyamine with water; and continuing to raise the temperature of the polyamine while continuing to sparge with a non-condensable gas and continuing to contact the polyamine with water.

Inventors: GOSSELINK EUGENE PAUL, GRAVES SHARON ANNE, HUTCHINS JAMES PEYTON, GOSSELINK, EUGENE, PAUL, GRAVES, SHARON, ANNE, HUTCHINS, JAMES, PEYTON
Applicants: PROCTER & GAMBLE, THE PROCTER & GAMBLE COMPANY
Application year: 1997
Main classification: C07C209
IPC codes: C07C209, C08G73