Patent GB-815122-A (GB)
Title: Improvements in or relating to curable polyurethane and polyurethane-polyurea polymers
IPC: C08L75/00
Filed: 1956-07-23
Abstract: The invention comprises curable polymers consisting essentially of the recurring units <FORM:0815122/IV (a)/1> wherein X is the bivalent radical resulting from the removal of the terminal chlorine atoms from a polymeric bischloroformate having a molecular weight of at least 875 and consisting of a polyalkyleneether bischloroformate, a polyalkyleneetherthioether bischloroformate, a polyalkylene-aryleneether bischloroformate, a polyalkylene - aryleneether - thioether bischloroformate or a polyaliphatic hydrocarbon bischloroformate; B is an alkylene or arylene radical; R is an alkyl, alkanol, alkenyl, alkenyl ether or alkenyl ester radical, with the proviso that when B is an alkylene radical, the R's on both sides of a B radical may be joined to form part of a diazacycloalkane ring; Q is a carbonyl radical or a non-polymeric diacyl radical; n is an integer greater than zero m is an integer including zero; the recurring units being connected by a Q or X radical; at least 60 per cent of the total weight of the polymer being the bivalent radicals X; said polymers having attached at least once for every 8000 units of molecular weight a side chain containing a hydroxyl group or an aliphatic C=C group.  Such polymers are obtained by interacting the corresponding polymeric bischloroformates, at least one secondary diamine of the formula RNH-B-NHR, and optionally also one or more compounds of the formula Cl-Q-Cl in the presence of an acid-acceptor, at least one of the reactants having a side chain containing a hydroxyl group or an aliphatic C=C group, the sum of the molar proportions of the bischloroformate and the compound Cl-Q-Cl being substantially equal to the molecular proportion of the secondary diamine.  The polymeric bischloroformates may have molecular weights between 875 and 10,000 and may be prepared by reacting the appropriate glycol with phosgene. Representative secondary amines are N,N1 - dimethyl - ethylenediamine, piperazine, N,N1-diallylethylenediamine, N,N1-di-(b -hydroxyethyl) ethylene diamine, 4,41-methylene - bis - (N - methylaniline), N,N1 - diethyl benzidine, N,N1-di-(b -hydroxyethyl)-p - phenylene diamine, 4,41 - (3 - butenylidene)-bis - (N - methylaniline) and N,N1 - diisobutylhexamethylene diamine.  For the preparation of the optional non-polymeric bischloroformate a number of glycols (mostly containing OH or C=C groups) is given. Preferred are the 1,3-propanediols of the formula <FORM:0815122/IV (a)/2> wherein X is a hydrocarbon radical having a terminal -CH=CH2 group. The polymers can be cured with an organic polyisocyanate (involving the side-chain OH groups) or by a sulphur curing procedure (involving the side-chain aliphatic C=C groups).  Polymers with 1,3-conjugated unsaturation can be cured in a Diels-Alder reaction with a bismaleimide such as m-phenylene bismaleimide.  When the polymer contains a cyclobutene ring (as in the case where in the polymers of the above formula the diacyl radical is derived from 1-methyl-cyclobutene - 2,3 - dicarbonyl chloride), curing may be effected merely by heating which causes cleavage of the cyclobutene ring.  In Example (1) a polytetramethylene ether bischloroformate is reacted with a mixture of piperazine and N,N1-di-(b -hydroxyethyl) ethylene diamine, and the polymer obtained is milled with carbon black and 3,31-dimethyl-4,41-biphenyl diisocyanate and cured under heat and pressure.  Generally similar examples are given which employ, as the secondary diamine: a mixture of N,N1-di-(b -hydroxyethyl) ethylene diamine and methylene-bis-(N-methylaniline); a mixture of N,N1-bis-(hydroxyethyl)-4,41-diaminodiphenyl ether and methylene-bis-(N-methylaniline); and N,N1-di-(b -hydroxyethyl) hexamethylene diamine.  In further Example (3) a polymer is obtained by reacting a polytetramethyleneether bischloroformate with N,N1-diallyl-ethylene diamine and is cured by milling with channel black, sulphur, dithiobisbenzothiazole and 2-mercapto-benzthiazole, followed by moulding under heat and pressure; (5) a polyalkylene ether glycol (prepared by reacting tetrahydrofuran and 1-allyloxy-2,3-epoxy propane in the presence of fluorosulphonic acid) is converted to the bischloroformate which, mixed with a polytetramethylene ether bis-chloroformate is reacted with piperazine.  The polymer obtained is sulphur cured; (7) a polymer from polytetramethyleneether bischloroformate, methylene bis - (N - methylaniline) and 9,10 - bis - (b  - hydroxyethylaminomethyl) anthracene is cured by heating with channel black and m-phenylenebismaleimide or with 3,31-dimethyl-4,41-biphenyl diisocyanate; (8) a polymer from polytetramethyleneether bischloroformate, N,N1-di - (b  - hydroxyethyl) ethylene diamine and methylene - bis - (N - methylaniline) is reacted with sorboyl chloride and then cured by heating with channel black and ethylene-bismaleimide or by sulphur-curing agents; (9) 2-[(allyloxy) methyl] - 2 - methyl - 1,3 - propane - bischloroformate is reacted with a polyurethane diamine obtained by reacting polytetramethylene ether bischloroformate with methylene-bis-(N-methylaniline).  The product is cured with sulphur curing agents; (11) the polyurethane diamine prepared as in (9) is reacted with 1-methylcyclobutene - 2,3 - dicarbonyl chloride.  The polymer is cured by heating with furnace black; (12) 4-allyloxy-N,N1-dimethyl-m-phenylene diamine and a polytetramethylene ether bischloroformate are reacted.  Part of the reaction product is treated with phosgene and then the remainder of the first reaction product is added and reaction continued.  The product is sulphur cured; (13) a polyhexyleneethyleneether-thioether glycol (obtained by reacting 1,6-hexanediol and thiodiglycol in the presence of p-toluene sulphonic acid is converted to the bischloroformate which is reacted with N,N1-diallyl ethylene diamine. The product is sulphur-cured.  Carbon black, clay, silica, esterified silica, talc, zinc and magnesium oxides, calcium and magnesium carbonates and titanium dioxide are suitable compounding agents.