Patent GB-1043341-A (GB)
Title: Improvements in or relating to modified polymeric materials and methods of producingsame
IPC: D06M13/272
Filed: 1963-01-07
Abstract: Polymers containing active hydrogen atoms may be modified in stages by reaction with an unsymmetrical polyfunctional compound having at least two functional groups having different reactivity under conditions whereby first one of said functional groups reacts with an active hydrogen atom of said polymers to link said compound to one molecule of said polymers and, if desired, subsequently subjecting said modified polymers to different reaction conditions whereby another different functional group of said unsymmetrical polyfunctional compound reacts with an active hydrogen atom of said polymers and links said unsymmetrical polyfunctional compound to another molecule of said polymers. Preferred polyfunctional reagents are those of the formula ROCH2CH(R1)-A1(Z-A11)n-R11 in which R represents hydrogen, C1- 6 alkyl or C2- 7 alkanoyl, R1 represents hydrogen or C1- 6 alkyl, A1 and A11 represent -CS-, -CO-, + -SO-, -SO2- or -S (R111)-, R111 represent a substituted or unsubstituted alkyl or aralkyl radical, Z represents alkylene, aralkylene, the residue of a diamine -N(R1)-Y-N(R1)- (in which Y is a divalent radical), the residue of a heterocyclic diamine <FORM:1043341/C3/1> in which the two nitrogen atoms are part of the heterocyclic ring D, the residue of a hydrazine radical -N(R1)-N(R1)- or an amine residue -N(R1)-, n is 0 or 1, R11 represents -C(R1)=CH(R1), -CH(R1)-CH(R1)-A, <FORM:1043341/C3/2> and A is a polar residue derived from a reagent of weak nucleophilic character, i.e. those which have an anion of a strong acid or a cation of a weak base.  In examples:  (a) viscose solution is modified by subjecting it to the first stage of the process and is then precipitated by addition to dilute H2SO4; (b) reactive sizes are prepared by applying the first stage of the process to corn starch or polyvinyl alcohol, the recovered product being boiled with water to form a size for application to a twist twill cotton fabric, which is then subjected to the second stage of the process, e.g. by heat curing; (c) corn starch is subjected to the first stage of the process in the presence of dioxane and aqueous NaOH, the recovered solid is dissolved in aqueous NaOH to give a gelatinous mass, which is cast into a film and cured to effect the second stage of the process; and (d) polyvinyl alcohol is subjected to the first stage of the process in the presence of dioxane and aqueous NaOH, the recovered solid is dissolved in a mixture of ethylene glycol and aqueous NaOH and cast into a film, which is then subsequently cured to effect the second stage of the process.ALSO:Polymers containing active hydrogen atoms may be modified in stages by reaction with an unsymmetrical polyfunctional compound having at least two functional groups having different reactivity under conditions whereby first one of said functional groups reacts with an active hydrogen atom of said polymers to link said compound to one molecule of said polymers and, if desired, subsequently subjecting said modified polymers to different reaction conditions whereby another different functional group of said unsymmetrical polyfunctional compound reacts with an active hydrogen atom of said polymers and links said unsymmetrical polyfunctional compound to another molecule of said polymers. Preferred unsymmetrical polyfunctional reagents are those of the formula:- ROCH2CH(R1)-A1(Z-A11)n-R11 in which R represents hydrogen, C1-6 alkyl or C2-7 alkanoyl, R1 represents hydrogen or C1-6 alkyl, A1 and A11 represent -CS-, -CO-, -SO-, -SO2- or -S(R111)-, R111 represents a substituted or unsubstituted alkyl or aralkyl radical, Z represents alkylene, aralkylene, the residue of a diamine -N(R1)-Y-N(R1)- (in which Y is a divalent radical), the residue of a heterocyclic didiamine -NDN- in which the two nitrogen atoms are part of the heterocyclic ring D, the residue of a hydrazine radical -N(R1)-N(R1)- or an amine residue -N(R1)-, n is 0 or 1, R11 represents -C(R1)=CH(R1), -CH(R1)-CH(R1)-A, <FORM:1043341/D1-D2/1> and A is a polar residue derived from a reagent of weak nucleophibic character, i.e. those which have an anion of a strong acid or a cation of a weak base.  The first stage of reaction with the polyfunctional reagent is preferably conducted in the presence of aqueous coustic soda at room temperature, moisture being retained in the material undergoing treatment by wrapping it in polyethylene sheeting.  The second stage of reaction may be carried out by heating, preferably in the presence of aqueous potassium bicarbonate, zinc fluoroborate or tetraethyl ammonium hydroxide.  The latter functions as a volatile catalyst and is removed by the simultaneous heating.  The above process may be used to impart wet and dry crease recovery to cellulosic fabrics and non-cellulosic fabrics such as wool, silk, polyamide and polyvinyl alcohol.  Viscose or cellulose acetate solutions may be treated to react one functional group of the unsymmetrical reagent, spun and then given the second stage of the treatment at the fibre, yarn or fabric stage.  Thus a final step may be carried out on pleated or creased garments after they have been made up, merely by heating or pressing.  Alternatively, a twisted or false-twisted cellulosic yarn may be obtained by carrying out the final stage of cross-linking while the yarn is in a super-twisted state and then applying a detwisting operation to give a permanently texturized yarn.  In examples (a) the first stage of the process is applied to cotton, viscose rayon and regenerated cellulose followed by an optional second step, which may take the form of creasing in a warp direction and ironing the crease at 150 DEG C.; (b) the first stage of the process is applied to cotton and rayon skeins which are then knitted into tubing and optionally subjected to the second stage of the process; (c) webs of cotton fibre are subjected to the first stage of the process the carded, drawn, spun and knitted before applying the second stage of the process; (d) spun rayon yarn is knitted into tubing, subjected to the first stage of the process, deknitted and used as a filling yarn for a fabric in which the warp is a semi-dull nylon yarn, the product being subsequently subjected to the second stage of the process; (e) reactive sizes are prepared by applying the first stage of the process to corn starch or polyvinyl alcohol, the recovered solid being boiled with water to form a size for application to a twist twill cotton fabric which is then subjected to the second stage of the process; and (f) cotton fabric is subjected to the first stage of the process, dyed with Atlantic Direct Sky Blue A and then subjected to the second stage of the process.