Methods of preparing sintered shapes and green bodies used therein

The invention relates to (1) a method of preparing sintered shapes, comprising the steps of forming a green body from a mixture comprising (A) a major amount of at least one inorganic powder with (B) at least one reaction product of a alkanolamine with a hydrocarbyl-substituted carboxylic acylating agent provided that when the hydrocarbyl group of the acylating agent contains less than 40 carbon atoms then the carboxylic acylating agent is a polycarboxylic acylating agent; and (2) sintering the body. Sintered shapes made from the methods of the present invention have relatively high fired densities and small uniform grain sizes; and low porosity. The reaction products of the present invention help disperse the inorganic powder. These reaction products also improve deagglomeration of the inorganic powder and help prevent reagglomeration of the powder.

TECHNICAL FIELD 
This invention relates to methods for preparing sintered articles. 
INTRODUCTION TO THE INVENTION 
Methods for the manufacturing of sintered shapes frequently involve the use 
of additives for controlling the powder/slurry dispersion, theology, green 
compaction, density, strength and grain size of the final shape. The 
objective generally is to achieve the highest possible density with a 
uniform, small grain size, and in the area of electronic substrates, to 
achieve an ultra-smooth surface. 
Many processes for preparing green bodys involve the preparation and use of 
slurries prepared by dispersing inorganic powders in liquids including, 
depending upon the application, water or organic liquids such as xylene, 
toluene, etc. The slurries of inorganic powders usually are prepared by 
milling a mixture containing the inorganic powder and the liquid. To 
improve the dispersion of the solids and maximize the solids concentration 
in the slurry and minimize slurry viscosity, dispersants have been added 
to obtain a complete dispersion of the powders in the liquid. 
OLOA 1200, available from Chevron Chemical Company, is a succinimide 
derived from polybutene and is useful as a surfactant, static stabilizer, 
emulsion agent and dispersant in ceramics applications. U.S. Pat. Nos. 
3,895,127; 4,654,075; 4,749,664; and 4,908,338 disclose the use of OLOA 
1200 in ceramics or glass production. Fowkes in "Dispersions of Ceramic 
Powders in Organic Media", Advances in Ceramics, volume 21, (1987) 
describes OLOA 1200 as being useful as a steric stabilizer in ceramics. 
Calvert et al in "Dispersion of Ceramic Particles in Organic Liquids" at 
Material Resource Society Symposium Volume 73 (1986) Materials Research 
Society, describes OLOA 1200 as having a chain length of about 60 carbon 
atoms. Calvert et al in "Dispersants in Ceramic Processing", British 
Ceramic Proceedings, published by British Ceramic Society, Vol. 37 (1986) 
describes OLOA 1200 as having a chain length of about 100 carbon atoms. 
U.S. Pat. No. 4,040,998 relates to an aqueous dispersion of ceramic slurry. 
The dispersion is prepared by mixing alumina, phenyl lower alkyl silicone 
resin and a flux with an alkylamine detergent in sufficient water to form 
a dispersion. 
SUMMARY OF THE INVENTION 
The invention relates to a method of preparing sintered shapes, comprising 
the steps of forming a green body from a mixture comprising (A) a major 
amount of at least one inorganic powder with (B) at least one reaction 
product of a alkanolamine and a hydrocarbyl-substituted carboxylic 
acylating agent provided that when the hydrocarbyl group of the acylating 
agent contains less than an average of 40 carbon atoms then the carboxylic 
acylating agent is a polycarboxylic acylating agent; and sintering the 
body. 
Sintered shapes made by the methods of the present invention have 
relatively high fired densities, small uniform grain sizes, and low 
porosity. The reaction products of the present invention help disperse the 
inorganic powder. These reaction products improve deagglomeration of the 
inorganic powder and help prevent reagglomeration of the powder. These 
reaction products are useful as dispersants, binders, lubricants, and 
emulsifiers in ceramics processing. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The term "hydrocarbyl" includes hydrocarbon, as well as substantially 
hydrocarbon, groups. Substantially hydrocarbon describes groups which 
contain non-hydrocarbon substituents which do not alter the predominately 
hydrocarbon nature of the group. 
Examples of hydrocarbyl groups include the following: 
(1) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), 
alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, aromatic-, 
aliphatic- and alicyclic-substituted aromatic substituents and the like as 
well as cyclic substituents wherein the ring is completed through another 
portion of the molecule (that is, for example, any two indicated 
substituents may together form an alicyclic radical); 
(2) substituted hydrocarbon substituents, that is, those substituents 
containing non-hydrocarbon groups which, in the context of this invention, 
do not alter the predominantly hydrocarbon substituent; those skilled in 
the art will be aware of such groups (e.g., halo (especially chloro and 
fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, 
sulfoxy, etc.); 
(3) hetero substituents, that is, substituents which will, while having a 
predominantly hydrocarbon character within the context of this invention, 
contain other than carbon present in a ring or chain otherwise composed of 
carbon atoms. Suitable heteroatoms will be apparent to those of ordinary 
skill in the art and include, for example, sulfur, oxygen, nitrogen and 
such substituents as, e.g., pyridyl, furyl, thienyl, imidazolyl, etc. In 
general, no more than about 2, preferably no more than one, 
non-hydrocarbon substituent will be present for every ten carbon atoms in 
the hydrocarbyl group. Typically, there will be no such non-hydrocarbon 
substituents in the hydrocarbyl group. Therefore, the hydrocarbyl group is 
purely hydrocarbon. 
Unless otherwise indicated, molecular weight is determined by gel 
permeation chromatography and the number of carbon atoms is derived from 
number average molecular weight. 
(A) Inorganic Powders 
Inorganic powders (A) used in the present invention include metallic and 
non-metallic powders. Powders may also be oxides or non-oxides of metallic 
or non-metallic elements. An example of metallic elements which may be 
present in the inorganic powders include calcium, magnesium, barium, 
scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, 
copper, zinc, yttrium, niobium, molybdenum, ruthenium, rhodium, silver, 
cadmium, lanthanum, actinium, gold or combinations of two or more thereof. 
In one embodiment, the inorganic powder may contain rare earth or 
ferromagnetic elements. The rare earth elements include the lanthanide 
elements having atomic numbers from 57 to 71, inclusive and the element 
yttrium, atomic number 39. Ferromagnetic metals, for purposes of this 
invention, include iron, nickel, cobalt and numerous alloys containing one 
or more of these metals. In another embodiment, the metals are present as 
alloys of two or more of the aforementioned elements. In particular, 
prealloyed powders such as low alloy steel, bronze, brass and stainless 
steel as well as nickel-cobalt based super alloys may be used as inorganic 
powders. 
The inorganic powders (A) may comprise inorganic compounds of one or more 
of the above-described metals. The inorganic compounds include ferrites, 
titanates, nitrides, carbides, borides, fluorides, sulfides, hydroxides 
and oxides of the above elements. Specific examples of the oxide powders 
include, in addition to the oxides of the above-identified metals, 
compounds such as beryllium oxide, magnesium oxide, calcium oxide, 
strontium oxide, barium oxide, lanthanum oxide, gallium oxide, indium 
oxide, selenium oxide, etc. Specific examples of oxides containing more 
than one metal, generally called double oxides, include perovskite-type 
oxides such as NaNbO.sub.3, SrZrO.sub.3, PbZrO.sub.3, SrTiO.sub.3, 
BaZrO.sub.3, BaTiO.sub.3 ; spinel-type oxides such as MgAl.sub.2 O.sub.4, 
ZnAl.sub.2 O.sub.4, CoAl.sub.2 O.sub.4, NiAl.sub.2 O.sub.4, NiCr.sub.2 
O.sub.4, FeCr.sub.2 O.sub.4, MgFe.sub.2 O.sub.4, ZnFe.sub.2 O.sub.4, etc.; 
illmenite-types oxides such as MgTiO.sub.3 MnTiO.sub.3, FeTiO.sub.3, 
CoTiO.sub.3, ZnTiO.sub.3, LiTaO.sub.3, etc.; and garnet-type oxides such 
as Gd.sub.3 Ga.sub.5 O.sub.12 and rare earth-iron garnet represented by 
Y.sub.3 Fe.sub.5 O.sub.12. The inorganic powder (A) may also be a clay. 
Examples of clays include kaolinite, nacrite, dickite, montmorillonite, 
montronite, spaponite, hectorite, etc. 
An example of non-oxide powders include carbides, nitrides, borides and 
sulfides of the metals described above. Specific examples of the carbides 
include SiC, TiC, WC, TaC, HfC, ZrC, AlC; examples of nitrides include 
Si.sub.3 N.sub.4, AlN, BN and Ti.sub.3 N.sub.4 ; and borides include 
TiB.sub.2, ZrB.sub.2 and LaB.sub.6. 
In one embodiment, the inorganic powder is silicon nitride, silicon 
carbide, zirconia, alumina, aluminum nitride, barium ferrite, 
barium-strontium ferrite or copper oxide. In another embodiment, the 
inorganic powder is alumina or clay. 
(B) Reaction Product Of Alkanolamines and Carboxylic Acylating Agents 
The methods of the present invention use, in addition to the 
above-described inorganic powder (A), at least one reaction product (B) of 
an alkanolamine with a hydrocarbyl-substituted carboxylic acylating agent 
provided that when the hydrocarbyl group of the acylating agent contains 
less than 40 carbon atoms, then the carboxylic acylating agent is a 
polycarboxylic acylating agent. The reaction products are included in the 
method of the present invention to assist in preparing green bodies and 
sintered shapes. The presence of the reaction product in the methods of 
the present invention facilitates the processing Of the powders and 
provides for increased solids loadings. Green bodies made by the present 
invention have improved green density, and reduced shrinkage. It is also 
possible to prepare slurries of inorganic powders in organic liquids 
containing high solids contents when the slurries contain at least one 
reaction product of the present invention. Generally, these slurries may 
contain greater than about 50%, greater than about 60%, or greater than 
about 70% by weight inorganic powder, based on the weight of the slurry. 
The amount of the reaction product of the present invention included in the 
methods of the present invention may be varied over a wide range depending 
upon the nature of the solid particles, the reaction product, and 
materials used to form the green body. Generally, the methods use from 
about 0.01%, preferably from about 0.1%, more preferably from about 0.2% 
to about 30%, preferably to about 10%, more preferably to about 5% by 
weight of the reaction product, based on the weight of inorganic powder in 
the composition. In another embodiment, the methods use from about 0.5% to 
about 15% by weight of the reaction product based on the weight of the 
inorganic powder, and in some cases, the compositions may contain as 
little as 0.2% to about 5% by weight of the reaction product based on the 
weight of the inorganic powder. 
Typically, the alkanolamines, which are reacted with the 
hydrocarbyl-substituted carboxylic acylating agent, include primary, 
secondary or tertiary alkanol amines or mixtures thereof. Such 
alkanolamines can be represented by the formulae: 
##STR1## 
wherein each R.sub.1 is independently a hydrocarbyl group of one to about 
eight carbon atoms or hydroxyhydrocarbyl group of one to about eight 
carbon atoms, preferably one to about four, and R" is a divalent 
hydrocarbyl group of about two to about 18 carbon atoms, preferably about 
two to about four The group --R"--OH in such formulae represents the 
hydroxyhydrocarbyl group. R" can be an acyclic, alicyclic or aromatic 
group. Typically, R" is an acyclic straight or branched alkylene group 
such as an ethylene, 1,2-propylene, 1,2-butylene, 1,2-octadecylene, etc., 
group. Where two R.sub.1 groups are present in the same molecule they can 
be joined by a direct carbon-to-carbon bond or through a heteroatom (e.g., 
oxygen, nitrogen or sulfur) to form a 5-, 6-, 7- or 8-membered ring 
structure. Examples of such heterocyclic amines include N-(hydroxyl lower 
alkyl)-morpholines, -thiomorpholines, -piperidines, -oxazolidines, 
-thiazolidines and the like. Typically, however, each R.sub.1 is 
independently a methyl, ethyl, propyl, butyl, pentyl or hexyl group. 
Examples of alkanolamines include mono-, di-, and triethanolamine, 
diethylethanolamine, ethylethanolamine, butyldiethanolamine, aminobutanol, 
aminomethylpropanol, aminopropanol, aminomethylpropanediol, 
aminoethylpropanediol, aminoethylheptanol and aminopentanol. 
The alkanolamines may also be an ether N-(hydroxyhydrocarbyl)amine. These 
are hydroxypoly(hydrocarbyloxy) analogs of the above-described 
alkanolamines (these analogs also include hydroxyl-substituted oxyalkylene 
analogs). Such N-(hydroxyhydrocarbyl) amines can be conveniently prepared 
by reaction of epoxides with aforedescribed amines and can be represented 
by the formulae: 
##STR2## 
wherein x is a number from about 2 to about 15 and R.sub.1 and R" are as 
described above. R.sub.1 may also be a hydroxypoly(hydrocarbyloxy) group. 
In another embodiment, the alkanolamine may be hydroxy-containing 
polyamines. Hydroxy-containing polyamine analogs of hydroxy monoamines, 
particularly alkoxylated alkylenepolyamines (e.g., N,N(diethanol)ethylene 
diamine) can also be used. Such polyamines can be made by reacting 
alkylene polyamines with one or more of the alkylene oxides such as 
ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, and 
styrene epoxide. Similar alkylene oxide-alkanol amine reaction products 
can also be used such as the products made by reacting the aforedescribed 
primary, secondary or tertiary alkanolamines with ethylene, propylene or 
higher epoxides in a 1.1 to 1.2 molar ratio. Reactant ratios and 
temperatures for carrying out such reactions are known to those skilled in 
the art. 
Specific examples of alkoxylated alkylenepolyamines include 
N-(2-hydroxyethyl) ethylenediamine, 
N,N-bis(2-hydroxyethyl)-ethylene-diamine, 1-(2-hydroxyethyl)piperazine, 
mono(hydroxypropyl)-substituted tetraethylenepentamine, 
N-(3-hydroxybutyl)-tetramethylene diamine, etc. Higher homologs obtained 
by condensation of the above-illustrated hydroxy-containing polyamines 
through amino groups or through hydroxy groups are likewise useful. 
Condensation through amino groups results in a higher amine accompanied by 
removal of ammonia while condensation through the hydroxy groups results 
in products containing ether linkages accompanied by removal of water. 
Mixtures of two or more of any of the aforesaid polyamines are also 
useful. 
The hydrocarbyl-substituted carboxylic acylating agent may be a 
monocarboxylic or polycarboxylic acylating agent provided that when the 
hyrocarbyl group of the carboxylic acylating agent contains less than an 
average of 40 carbon atoms, then the carboxylic acylating agent is a 
polycarboxylic acylating agent. The acylating agents may be a carboxylic 
acid or derivatives of the carboxylic acid such as the halides, esters, 
anhydrides, etc. In one embodiment, the carboxylic acylating agent is a 
succinic acylating agent. 
The hydrocarbyl group of the carboxylic acylating agent generally contains 
an average of about 8, preferably about 10 to about 500, preferably about 
300 carbon atoms. In one embodiment, the hydrocarbyl group contains an 
average of about 8, preferably about 10, more preferably about 12 to about 
40, preferably about 30, more preferably about 24 carbon atoms. In another 
embodiment the hydrocarbyl group contains an average of greater than 40 
carbon atoms. In this embodiment, the hydrocarbyl group generally contains 
from about 50, preferably about 60 to about 300, preferably about 200 
carbon atoms. In one embodiment, the hydrocarbyl group is derived from a 
polyalkene having a number average molecular weight (Mn) of about 500, 
preferably about 700, more preferably about 800 to about 5000, preferably 
about 3000, more preferably about 2000. Number average molecular weight is 
determined by gel permeation chromatography. 
The hydrocarbyl group may be derived from one or more olefins having from 
about 8, preferably about 10, more preferably about 12, to about 40, 
preferably to about 30, more preferably to about 24 carbon atoms. These 
olefins are preferably alpha-olefins (sometimes referred to as 
mono-1-olefins) or isomerized alpha-olefins. Examples of the alpha-olefins 
include 1-octene, 1-nonene, 1-decene, 1-dodecene, 1-tridecene, 
1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 
1-nonadecene, 1-eicosene, 1-henicosene, 1-docosene, 1-tetracosene, etc. 
Commercially available alpha-olefin fractions that can be used include the 
C.sub.15-18 alpha-olefins, C.sub.12-16 alpha-olefins, C.sub.14-16 
alpha-olefins, C.sub.16-18 alpha-olefins, C.sub.16-18 alpha-olefins, 
C.sub.16-20 alpha-olefins, C.sub.22-28 alpha-olefins, etc. The C.sub.16 
and C.sub.16-18 alpha-olefins are particularly preferred. 
Isomerized alpha-olefins are alpha-olefins that have been converted to 
internal olefins. The isomerized alpha-olefins suitable for use herein are 
usually in the form of mixtures of internal olefins with some 
alpha-olefins present. The procedures for isomerizing alpha-olefins are 
well known to those in the art. Briefly these procedures involve 
contacting alpha-olefin with a cation exchange resin at a temperature in a 
range of about 80.degree. to about 130.degree. C. until the desired degree 
of isomerization is achieved. These procedures are described for example 
in U.S. Pat. No. 4,108,889 which is incorporated herein by reference. The 
succinic acylating agents are prepared by reacting the above-described 
olefins or isomerized olefins with unsaturated carboxylic acids such as 
fumaric acids or maleic acid or anhydride at a temperature of about 
160.degree. to about 240.degree. C., preferably about 185.degree. to about 
210.degree. C. Free radical initiators (e.g., t-butyl catechol) can be 
used to reduce or prevent the formation of polymeric byproducts. The 
procedures for preparing the acylating agents are well known to those 
skilled in the art and have been described for example in U.S. Pat. No. 
3,412,111; and Ben et al, "The Ene Reaction of Maleic Anhydride With 
Alkenes", J. C. S. Perkin II (1977), pages 535-537, These references are 
incorporated by reference for their disclosure of procedures for making 
the above acylating agents. 
In another embodiment, the hydrocarbyl-substituted carboxylic acylating 
agent may have a hydrocarbyl group derived from a polyalkene. The 
polyalkenes include polyalkenes containing at least an average of about 50 
carbon atoms, preferably at least about 60, more preferably at least about 
65 to about 500 carbon atoms, preferably to about 300, more preferably to 
about 200. In one embodiment, the polyalkene is characterized by an Mn 
(number average molecular weight) value of at least about 1600. Generally, 
the polyalkene is characterized by an Mn value from about 700, preferably 
from about 800, more preferably from about 900 to about 5000, preferably 
to about 3000, more preferably to about 2500. In another embodiment, the 
polyalkene is characterized as having a Mn value of about 700, preferably 
about 800 to about 2000, preferably about 1500. 
In another embodiment the hydrocarbyl groups are derived from polyalkenes 
having an Mn value in the above-described ranges and an Mw/Mn value from 
about 1.5, preferably from about 1.8, more preferably about 2.5 to about 
4, preferably to about 3.6, more preferably to about 3.2. The term Mw 
refers to weight average molecular weight. The preparation and use of 
substituted succinic acylating agents wherein the substituent is derived 
from such polyolefins are described in U.S. Pat. No. 4,234,435, the 
disclosure of which is hereby incorporated by reference. 
The polyalkenes include homopolymers and interpolymers of polymerizable 
olefin monomers of 2 to about 16 carbon atoms, preferably to about 6 
carbon atoms. The olefins may be monoolefins such as ethylene, propylene, 
1-butene, isobutene, and 1-octene; or a polyolefinic monomer, preferably 
diolefinic monomer, such 1,3-butadiene and isoprene. Usually the monomers 
contain from 2 to about 6 carbon atoms, preferably to about 4, more 
preferably 4. The interpolymers include copolymers, terpolymers, 
tetrapolymers and the like. Preferably, the interpolymer is a homopolymer. 
An example of a preferred homopolymer is a polybutene, preferably a 
polybutene in which about 50% of the polymer is derived from isobutylene. 
The polyalkenes are prepared by conventional procedures. 
The hydrocarbyl-substituted acylating agents are prepared by a reaction of 
one or more polyalkene or olefin with one or more unsaturated carboxylic 
reactants. The unsaturated carboxylic reactants may contain one or more 
carboxyl groups, preferably one to about four, more preferably one or two. 
Examples of unsaturated carboxylic reactants containing one carboxyl group 
include acrylic, methacrylic or crotonic acids or derivatives thereof. 
Examples of unsaturated carboxylic reactants having two carboxyl groups 
include maleic, fumaric, itaconic, citraconic acids and derivatives 
thereof, preferably maleic or fumaric acids or derivatives thereof. 
The hydrocarbyl-substituted acylating agents may be prepared by reacting a 
polyalkene or an olefin with the unsaturated carboxylic reactant such that 
there is at least one mole of unsaturated reactant for each mole of 
polyalkene or olefin. Preferably, an excess of unsaturated carboxylic 
reactant is used. This excess is generally between about 5% to about 25%. 
In another embodiment, the acylating agents are prepared by reacting the 
above described polyalkene with an excess of maleic anhydride to provide 
hydrocarbyl-substituted succinic acylating agents wherein the number of 
succinic groups for each equivalent weight of substituent group is at 
least 1.3. The maximum number generally will not exceed 4.5. A suitable 
range is from about 1.4 to about 3.5 and more specifically from about 1.4 
to about 2.5 succinic groups per equivalent weight of substituent groups. 
In this embodiment, the polyalkene preferably has an Mn from about 1400 to 
about 5000 and a Mw/Mn of at least 1.5, as described above. A more 
preferred range for Mn is from about 1500 to about 2800, and a most 
preferred range of Mn values is from about 1500 to about 2400. 
The conditions, i.e., temperature, agitation, solvents, and the like, for 
reacting an unsaturated carboxylic reactant with a polyalkene, are known 
to those in the art. Examples of patents describing various procedures for 
preparing useful acylating agents include U.S. Pat. No. 3,215,707 (Rense); 
U.S. Pat. No. 3,219,666 (Norman et al); U.S. Pat. No. 3,231,587 (Rense); 
U.S. Pat. No. 3,912,764 (Palmer); U.S. Pat. No. 4,110,349 (Cohen); and 
U.S. Pat. No. 4,234,435 (Meinhardt et al); and U.K. 1,440,219. The 
disclosures of these patents are hereby incorporated by reference. 
In another embodiment, the carboxylic acylating agent is an 
alkylalkyleneglycol-acetic acid, more preferably 
alkylpolyethyleneglycol-acetic acid. Some specific examples of these 
compounds include: iso-stearylpentaethyleneglycol-acetic acid; 
iso-stearyl-O-(CH.sub.2 CH.sub.2 O).sub.5 CH.sub.2 CO.sub.2 Na; 
lauryl-O-(CH.sub.2 CH.sub.2 O).sub.5 -CH.sub.2 CO.sub.2 H; 
lauryl-O-(CH.sub.2 CH.sub.2 O).sub.3.3 CH.sub.2 CO.sub.2 H; 
oleyl-O-(CH.sub.2 C-H.sub.2 O).sub.4 -CH.sub.2 CO.sub.2 H; 
lauryl-O-(CH.sub.2 CH.sub.2 O).sub.4.5 CH.sub.2 CO.sub.2 H; 
lauryl-O-(CH.sub.2 CH.sub.2 O)-.sub.10 CH.sub.2 CO.sub.2 H; 
lauryl-O-(CH.sub.2 CH.sub.2 O).sub.16 CH.sub.2 CO.sub.2 H; 
octyl-phenyl-O-(CH.sub.2 CH.sub.2 O).sub.8 CH.sub.2 CO.sub.2 H; 
octyl-phenyl-O-(CH.sub.2 CH.sub.2 O).sub.19 CH.sub.2 CO.sub.2 H; 
2-octyl-decanyl-O-(CH.sub.2 CH.sub.2 O).sub.6 CH.sub.2 CO.sub.2 H. These 
acids are available commercially from Sandoz Chemical under the tradename 
Sandopan acids. 
The acylating agent may also be an aromatic carboxylic acylating agent, 
such as aromatic carboxylic acid. A group of useful aromatic carboxylic 
acids are those of the formula 
##STR3## 
wherein R is a hydrocarbyl group as defined above; (a), (b) and (c) are 
each independently an integer from 1 up to 3 times the number of aromatic 
nuclei are present Ar with the proviso that the sum of (a) plus (b) plus 
(c) does not exceed the unsatisfied valencies of Ar; and Ar is 
independently an aromatic moiety which has from 0 to 3 substituents 
selected from the group consisting of lower alkyl, alkoxyl, nitro, halo or 
combinations of two or more thereof. The number of aromatic nuclei, fused, 
linked or both, in the above-described Ar can play a role in determining 
the integer values of a, b and c. For example, when Ar contains a single 
aromatic nucleus, a, b and c are each independently 1 to 4. When Ar 
contains two aromatic nuclei, a, b and c can each be an integer from 1 to 
8, that is, up to three times the number of aromatic nuclei present (in 
naphthalene, 2). With a tri-nuclear aromatic moiety (Ar), a, b and c can 
each be an integer of 1 to 12. For instance, when Ar is a biphenyl or a 
naphthyl moiety, a, b and c can each independently be an integer of 1 to 
8. The values of a, b and c are limited by the fact that their sum cannot 
exceed the total unsatisfied valences of Ar. 
The aromatic moiety, Ar, can be a single aromatic nucleus such as a benzene 
nucleus, a pyridine nucleus, a thiophene nucleus, a 
1,2,3,4-tetrahydronaphthalene nucleus, etc., or a polynuclear aromatic 
moiety. Such polynuclear moieties can be of the fused type; that is, 
wherein at least two aromatic nuclei are fused at two points to another 
nucleus such as found in naphthalene, anthracene, the azonaphthalenes, 
etc. Such polynuclear aromatic moieties also can be of the linked type 
wherein at least two nuclei (either mono or polynuclear) are linked 
through bridging linkages to each other. Such bridging linkages can be 
chosen from the group consisting of carbon-to-carbon single bonds, ether 
linkages, keto linkages, sulfide linkages, polysulfide linkages of 2 to 6 
sulfur atoms, sulfinyl linkages, sulfonyl linkages, methylene linkages, 
alkylene linkages, di-(lower alkyl)methylene linkages, lower alkylene 
ether linkages, alkylene keto linkages, lower alkylene sulfur linkages, 
lower alkylene polysulfide linkages of 2 to 6 carbon atoms, amino 
linkages, polyamino linkages and mixtures of such divalent bridging 
linkages. In certain instances, more than one bridging linkage can be 
present in Ar between aromatic nuclei. For example, a fluorene nucleus has 
two benzene nuclei linked by both a methylene linkage and a covalent bond. 
Such a nucleus may be considered to have 3 nuclei but only two of them are 
aromatic. Normally, Ar will contain only carbon atoms in the aromatic 
nuclei per se. 
Within this group of aromatic acids, a useful class of carboxylic acids are 
those of the formula 
##STR4## 
wherein a, b, c and R are defined above, a is a number in the range of 
from zero to about 4, preferably 1 to about 3; b is a number in the range 
of 1 to about 4, preferably 1 to about 2, c is a number in the range of 
zero to about 4, preferably 1 to about 2, and more preferably 1; with the 
proviso that the sum of a, b and c does not exceed 6. Preferably, b and c 
are each one and the carboxylic acid is a salicylic acid. The salicylic 
acids preferably are aliphatic hydrocarbon-substituted salicyclic acids 
wherein each aliphatic hydrocarbon substituent contains an average of at 
least about 8 carbon atoms per substituent and 1 to 3 substituents per 
molecule. 
The above aromatic carboxylic acids are well known or can be prepared 
according to procedures known in the art. Carboxylic acids of the type 
illustrated by these formulae and processes for preparing their neutral 
and basic metal salts are well known and disclosed, for example, in U.S. 
Pat. Nos. 2,197,832; 2,197,835; 2,252,662; 2,252,664; 2,714,092; 
3,410,798; and 3,595,791. 
The above reaction products of an alkanolamine and a 
hydrocarbyl-substituted carboxylic acylating agent may be post-treated 
with one or more post-treating reagents selected from the group consisting 
of boron trioxide, boron anhydrides, boron halides, boron acids, boron 
amides, esters of boric acids, carbon disulfide, hydrogen sulfide, sulfur, 
sulfur chlorides, alkenyl cyanides, carboxylic acid acylating agents, 
aldehydes, ketones, urea, thiourea, guanidine, dicyanodiamide, hydrocarbyl 
phosphates, hydrocarbyl phosphites, hydrocarbyl thiophosphates, 
hydrocarbyl thiophosphites, phosphorus sulfides, phosphorus oxides, 
phosphoric acid, hydrocarbyl thiocyanates, hydrocarbyl isocyanates, 
hydrocarbyl isothiocyanates, epoxides, episulfides, formaldehyde or 
formaldehyde-producing compounds with phenols, and sulfur with phenols. 
The following U.S. patents are expressly incorporated herein by reference 
for their disclosure of posttreating processes and post-treating reagents: 
U.S. Pat. Nos. 3,087,936; 3,254,025; 3,256,185; 3,278,550; 3,282,955; 
3,284,410; 3,338,832; 3,533,945; 3,639,242; 3,708,522; 3,859,318; 
3,865,813; etc. U.K. Patent Nos. 1,085,903 and 1,162,436 also describe 
such processes. 
In one embodiment, the reaction product are post-treated with at least one 
boron compound. The reaction of the reaction product with the boron 
compounds can be effected simply by mixing the reactants at the desired 
temperature. Ordinarily it is preferably between about 50.degree. C. and 
about 250.degree. C. In some instances it may be 25.degree. C. or even 
lower. The upper limit of the temperature is the decomposition point of 
the particular reaction mixture and/or product. 
The amount of boron compound reacted with one of reaction product generally 
is sufficient to provide from about 0.1 to about 10 atomic proportions of 
boron for each equivalent of the reaction product, such as the atomic 
proportion of nitrogen or hydroxyl group of the reaction product. The 
preferred amounts of reactants are such as to provide from about 0.5 to 
about 2 atomic proportions of boron for each equivalent of reaction 
product. To illustrate, the amount of a boron compound having one boron 
atom per molecule to be used with one mole of an amine reaction product 
having five nitrogen atoms per molecule is within the range from about 0.1 
mole to about 50 moles, preferably from about 0.5 mole to about 10 moles. 
The following examples relate to carboxylic acylating agents and their 
reaction with at least one alkanol amine. Unless otherwise indicated in 
the following examples, as well as elsewhere in the specification and 
claims, all percentages and parts are by weight, temperature is in degrees 
Celsius and pressure is atmospheric pressure.

EXAMPLE 1 
A reaction vessel is charged with 1000 parts of polyisobutenyl (Mn=950) 
substituted succinic anhydride heated in a resin kettle with stirring to 
about 90.degree. C. is slowly added over a two hour period 209 parts of 
N,N-diethylethanol amine. Heating is continued for an additional hour at 
90.degree. C. The heated reaction mixture is cooled to room temperature to 
provide the desired product. 
EXAMPLES 2-10 
Examples 2-10 are prepared by the procedure described in Example 1. The 
carboxylic acylating agent is reacted with the alkanolamine on an equal 
molar basis. 
__________________________________________________________________________ 
EXAMPLE NUMBER 
CARBOXYLIC ACYLATING AGENT 
ALKANOLAMINE 
__________________________________________________________________________ 
2 Hexadecenyl Succinic Anhydride 
Amino-methyl propanol 
3 Tetrapropenyl Succinic Anhydride 
Diethanolamine 
4 Polybutenyl (-- Mn = 1690) Succinic Anhydride 
Triethanolamine 
5 Hexadecenyl Succinic Anhydride 
N,N-diethylethanolamine 
6 16-18 Substituted Succinic Anhydride 
N,N-diethylethanolamine 
7 Polybutenyl (-- Mn = 960) Succinic Anhydride 
Aminopropanol 
8 Polybutenyl (-- Mn = 960) Succinic Anhydride 
Triethanolamine 
9 Isostearylpentaethylene glycol-Acetic Acid 
Ethanolamine 
10 Polybutenyl (-- Mn = 960) Salicylic Acid 
N,N-diethylethanolamine 
__________________________________________________________________________ 
Organic Binder 
Binders may be included in the compositions to facilitate the production of 
green bodies whether the bodies are produced by extrusion or injection 
molding, press molding or slip casting or other methods. 
The amount of binder included in the compositions of the present invention 
is an amount which provides the desired properties for the green and 
sintered shapes. Generally, the compositions will contain about 5% by 
weight of the binder based on the weight of the inorganic powder although 
larger amounts, such as to about 30% by weight, can be utilized in some 
applications. The binder may be present in amounts greater than 0.5% by 
weight based on the inorganic powder. 
A variety of binders have been suggested and utilized in the prior art and 
can be utilized in the methods and compositions of the present invention. 
Examples these binders include starch, cellulose derivatives, polyvinyl 
alcohols, polyvinylbutyral, etc. Examples of synthetic resin binders 
include thermoplastic materials such as polystyrene, polyethylene, 
polypropylene and mixtures thereof. 
Other binders which are useful in the composition of the invention include 
vegetable oils, petroleum jelly and various wax-type binders which may be 
hydrocarbon waxes or oxygen-containing hydrocarbon waxes. Examples of 
hydrocarbon waxes include petroleum waxes such as paraffin wax, 
microcrystalline wax, petrolatum, etc., synthetic hydrocarbons such as 
Fischer-Tropsch wax, low molecular weight polyethylene, etc. Examples of 
oxygen- containing waxes include higher fatty acids and esters and 
glycerides of the higher fatty acids with a higher alcohol, and 
oxygen-containing compounds obtained by air-oxidation of normal paraffin 
or isoparaffin such as alcohols, ketones, carboxylic acids, oxycarboxylic 
acids, keto carboxylic acids, esters, lactones, etc. The oxygen-containing 
wax-type binders may be natural waxes and/or synthetic waxes. The natural 
waxes include animal waxes such as bees wax, whale wax, China wax, wool 
wax; vegetable waxes such as candelilla wax, carnuba wax, Japan wax, 
sugarcane wax, etc.; and mineral waxes such as montan wax, ozokerite wax, 
lignite wax, etc. Examples of synthetic oxygen-containing wax-type binders 
include modified waxes such as montan wax derivatives, paraffin wax 
derivatives, microcrystalline wax derivatives, etc.; higher monohydric 
alcohols such as cetyl alcohol, stearyl alcohol, myristyl alcohol, lauryl 
alcohol, etc.; higher fatty acids such as capric acic, lauric acid, 
palmitic acid, stearic acid, etc. Mixtures of any of the above waxes also 
can be utilized as binders in the present invention. 
In one embodiment, the reaction products (B) improve the dispersion of wax 
binders in hot water, prior to addition of the dispersion to the ceramic 
powder. This eliminates the need to preheat ceramic slips when a wax 
binder is used. 
Sintering Aids 
"Sintering aids" may be organic or inorganic materials which improve the 
properties of the final sintered products. Examples of inorganic materials 
include the hydroxides, oxides or carbonates of alkali metals, alkaline 
earth metals, and the transition metals including, in particular, the rare 
earth elements. Specific examples of inorganic sintering aids include 
calcium oxide, magnesium oxide, calcium carbonate, magnesium carbonate, 
zinc oxide, zinc carbonate, yttrium oxide, yttrium carbonate, zirconium 
oxide, zirconium carbonate, lanthanum oxide, neodymium oxide, samarium 
oxide, etc. In another embodiment, overbased and gelled overbased metal 
salts may be used as sintering aids. Overbased metal salts are 
characterized by metal content in excess of that which would be present 
according to stoichiometry of metal in the particular organic compound 
reacted with the metal. Typically, a metal salt is reacted with an acidic 
organic compound such as a carboxylic, sulfonic, phosphorus, phenol or 
mixtures thereof. An excess of metal is incorporated into the metal salt 
using an acidic material, typically carbon dioxide. Gelled overbased metal 
salts are prepared by treating an overbased metal salt with a conversion 
agent, usually an active hydrogen-containing compound. Conversion agents 
include lower aliphatic carboxylic acids or anhydrides, water, aliphatic 
alcohols, cycloaliphatic alcohols, aryl aliphatic alcohols, phenols, 
ketones, aldehydes, amines and the like. The overbased and gelled 
overbased metal salts are known and described in U.S. Pat. No. 3,492,231 
issued to McMillen which is hereby incorporated by reference for its 
disclosure to overbased and gelled overbased metal salts and processes for 
making the same. 
Small amounts of the sintering aids generally are sufficient to provide the 
desired improvement in strength, thermal conductivity and/or density of 
the sintered shapes, thus, amounts of from about 0.05%, preferably about 
0.1% to about 10%, preferably to about 5%, by weight of the sintering aid, 
based on the weight of the inorganic powder, are sufficient. 
Liquid Dispersing Medium 
The compositions of the present invention also may contain, and generally 
do contain a liquid dispersing medium. It is an important aspect of this 
invention, however, that mixtures, dispersions and/or slurries prepared 
with the compositions of the present invention are homogeneous, 
substantially free of agglomerated inorganic powder particles, and stable. 
It also is preferred that the liquid dispersing medium be volatile under 
the conditions of drying or binder burnout prior to the early stages of 
sintering so that the medium does not interfere with the preparation of 
compacted inorganic shapes characterized by desirable densities and the 
absence of cracks and other defects. The medium can have components 
characterized by relatively low boiling points such as, for example, in 
the range of about 25.degree. C. to about 120.degree. C. to facilitate 
subsequent removal of a portion or substantially all of the medium from 
the compositions of the invention. Alternatively, the medium may contain 
components that have higher boiling points to protect against removal from 
such compositions upon standing or initial heating. There is no 
criticality in an upper boiling point limitation on these liquids except, 
as noted above, the liquids should be removable prior to the initial 
sintering process. 
The liquid dispersing medium may be oxygenated or hydrocarbon in nature. 
Oxygenated solvents include alcohols, esters, ketones and water as well as 
ethoxylated versions of the same. Combinations of these materials are also 
useful. Alcohols include alcohols having less than 12 carbon atoms, 
especially lower alkanols, such as methanol, ethanol, propanol and 
butanol. Esters include carboxylic esters prepared from carboxylic acids 
having from 2 to 20 carbon atoms and alcohols having from 1 to about 22 
carbon atoms. Examples of carboxylic esters include methylacetate, 
ethylacetate, propylacetate. Ketones include methylethyl ketone, 
methylisobutyl ketone as well as keto alcohols such as diacetone alochol, 
hydroxy acetone, hydroxymethylpentanone and the like. Tetrahydrofuran may 
also be used as a liquid dispersing medium. 
The oxygenated dispersing media include alkoxy alcohols which are 
characterized as having ether linkages and may be prepared by using 
alkylene oxides having from 2 to about 10 carbons atoms, such as ethylene 
oxide, propylene oxide and the like. Alkoxy alcohols are available 
commercially under trade names such as Cellosolve.TM., Propasol.TM., 
Carbitol.RTM. solvents available from Union Carbide. Examples of these 
materials include ethylene glycol monoethyl, monopropyl, monobutyl or 
monohexyl ethers, propylene glycol monomethyl, monoethyl, monopropyl, 
monobutyl and monohexyl ethers and the like. Alkoxy alcohols also include 
polyoxyalkylene glycols such as Carbowax.RTM. PEG 300, 600, 1000 and 1450 
available from Union Carbide Corporation. Polyoxypropylene glycols are 
also useful, such as Nyax 425 and Nyax 1025 available from Union Carbide 
and PPG-1200 and PPG-2000 available from Dow Chemical. Polyoxyalkylene 
polyols such as "TRITON.RTM." available from Rohm & Haas Company, 
"CARBOWAX.RTM." and "TERGITOL.RTM." available from Union Carbide, 
"ALFONIC.RTM." available from Conoco Chemical Company and "NEODOL.RTM." 
available from Shell Chemical are useful as liquid dispersing media. 
Alkyl, cycloalkyl and aryl hydrocarbons, as well as petroleum fractions may 
also be used as liquid media in this invention. Included within these 
types are benzene and alkylated benzenes, cycloalkanes and alkylated 
cycloalkanes, cycloalkenes and alkylated cycloalkenes such as found in the 
naphthene-based petroleum fraction, and the alkanes such as found in the 
paraffin-based petroleum fractions. Petroleum ether, naphthas, mineral 
oils, Stoddard Solvent, toluene, xylene, etc., and mixtures thereof are 
examples of economical sources of suitable liquid disperse medium. 
The amount of liquid dispersing medium utilized in the compositions of the 
present invention may vary over a wide range although it is generally 
desirable to prepare compositions containing a maximum amount of the 
inorganic powder and a minimum amount of the disperse medium. The amount 
of liquid disperse medium utilized in any particular combination can be 
readily determined by one skilled in the art will depend upon the nature 
of the inorganic powder, the type and amount of dispersant, and any other 
components present in the composition. The amount of liquid dispersed 
medium present is usually from as low as 1-2%, generally about 5%, 
preferably about 10%, more preferably about 15%, to about 40%, preferably 
about 35%, more preferably about 30% by weight based on the amount of 
inorganic powder (A). 
Other Additives 
Other materials may be added to the compositions of the present invention. 
For example, plasticizers may be added to the compositions to provide more 
workable compositions. Examples of plasticizers normally utilized in 
inorganic formulations include dioctyl phthalate, dibutyl phthalate, 
benzyl butyl phthalate and phosphate esters. 
Preparation 
The preparation of inorganic shapes utilizing the methods of the present 
invention generally involves mixing the inorganic powder with the reaction 
product (B). The mixture can be prepared either in the absence or presence 
of a volatile liquid dispersing medium. Any of the optional components 
described above can be mixed with the inorganic powder and the polymer at 
this stage. The mixed composition then is blended in, for example, a 
ball-mill where additional components can be added and blended into the 
mixture as desired. The blended mixture can then be shaped in a mold, a 
still water press, or sheet mold. Alternatively, the blended mixture can 
be extrusion- or ejection-molded to form a green body, or the mixture can 
be prepared by casting the mixture on a tape. The green body may also be 
prepared by spray-drying rotary evaporation, etc. Following the formation 
of the mixture into the desired shape, the shaped mass is subjected to 
elevated temperature treatment (sintering). 
The heat treatment is a high-temperature treatment at which time the 
inorganic powders are sintered resulting in the formation of a shape 
having the desired properties including suitable densities. For powder 
metallurgy, the sintering generally occurs between about 260.degree. C. to 
about 2100.degree. C., typically to about 1000.degree. C. For ceramic 
processes, the sintering generally occurs from abougt 600.degree. C., 
preferably about 700.degree. C. up to about 1700.degree. C. When the 
inorganic powders (A) are oxide powders, baking and sintering can be 
effected in the presence of oxygen. However, when the inorganic powders 
are non-oxide powders such as the nitrides and carbides, sintering is 
effected in a nonoxidizing atmosphere such as an atmosphere of hydrogen, 
argon or nitrogen gas. 
In one embodiment, the shaped mass is heated to a temperature which is 
sufficient to remove volatile materials from the green body. That is, the 
shape is heated to a temperature which is sufficient to vaporize and/or 
decompose organic materials from the body. This 15 heating step, often 
referred to as drying or binder burnout, takes place at moderately 
elevated temperatures, and is generally completed at a temperature below 
about 700.degree. C. 
Removal of organic materials is generally carried out under conditions 
which provide for the removal of the organic materials before the 
inorganic powders are subjected to sintering. 
In another embodiment, the organic materials, including binder, may be 
removed by solvent extraction. The solvent extraction may also be super 
critical solvent extraction, i.e., at high temperature and pressure. 
Generally, the green body is heated to above the flow point of the binder 
and exposed to solvent vapor. The green body may also be submerged in a 
solvent bath. In one embodiment, the green body is exposed to solvent 
extraction and then undergoes drying (burn out) to remove the organic 
materials. The solvents useful for extraction include liquid dispersing 
media described above. Alcohols, alkanes, such as hexane, pentane, octane, 
etc., and aromatic fractions including toluene and xylene are particularly 
useful. 
U.S. Pat. Nos. 4,961,913 and 4,197,118 describe solvent extraction 
processes for ceramics and are hereby incorporated by reference for that 
disclosure. 
While the invention has been explained in relation to its preferred 
embodiments, it is to be understood that various modifications thereof 
will become apparent to those skilled in the art upon reading the 
specification. Therefore, it is to be understood that the invention 
disclosed herein is intended to cover such modifications as fall within 
the scope of the appended claims.