Patent GB-871762-A (GB)
Title: Polyurethane plastics and their production
IPC: C08G18/48
Filed: 1958-11-06
Abstract: In a process for the production of polyurethane foam plastics a linear polyalkylene ether glycol which has been modified by the replacement of at least one of the two terminal hydroxyl groups by a group OR in which R is an organic radical containing at least two hydroxyl groups is reacted with an excess of polyisocyanate and with water.  The modified polyalkylene ether glycol can be obtained by the reaction of a polyalkylene ether glycol with an epoxide or glycidyl ether each containing free hydroxyl groups or by reaction of the polyalkylene ether glycol with an epoxy compound containing a halogen atom with subsequent replacement of the halogen atom by a hydroxy group.  The modified polyalkylene ether glycol may be first reacted with the polyisocyanate, the resulting product then being reacted with water.  The polyalkylene ether glycols may be those obtained by condensing an alkylene oxide having 2-5 carbon atoms, by the reaction of such alkylene oxides with polyvalent alcohols such as 1, 4-butylene glycol, glycerol, trimethylol propane or pentaerythritol or by polymerization of tetrahydrofuran.  Modification of these glycols may be effected by reaction (preferably at 30 DEG -130 DEG C. in the presence of catalysts such as boron fluoride etherate or perchloric acid) with such epoxides as the 1, 2-epoxide of glycerol, pentaerythritol monoepoxide, or the oxide of trimethylol propane; or with glycidyl ethers having free hydroxyl groups, such as those obtained by reacting a polyhydric alcohol (e.g. glycol, diethylene glycol, glycerol, hexanetriol or trimethylol propane) with epichlorhydrin in such amount that not all the OH groups are etherified.  Another method is to react the polyglycol with epichlorhydrin to give a product containing hydroxyl and chlorine atoms and replacing the chlorine by hydroxyl by boiling with an alkali.  Suitable polyisocyanates are listed.  Tertiary amines and organic compounds are suitable catalysts.  Sulphonated hydrocarbons or castor oil, fillers, dyes, and silicone oil are other suitable additives.  In Examples (1) an adduct prepared by reacting a linear polypropylene glycol (M.Wt. 2000) with 2 mols of glycerine-1, 2-oxide in the presence of BF3 etherate is reacted with toluylene diisocyanate.  The product is foamed by adding a mixture of dimethyl benzylamine, paraffin oil and water; (2) an adduct prepared by the reaction of the polypropylene glycol with 2 mols of epichlorhydrin and saponification of CH2Cl groups in the product to -CH2OH groups, is reacted with toluylene diisocyanate. The product is converted to a foam material by adding diethylene triamine, silicone oil and water. Specifications 769,680 and 769,682 are referred to.ALSO:In a process for the production of polyurethane foam plastics a linear polyalkylene ether glycol which has been modified by the replacement of at least one of the two terminal hydroxyl groups by a group OR in which R is a radical containing at least two hydroxyl groups is reacted with an excess of polyisocyanate and water.  The modified polyalkylene ether glycol can be obtained by the reaction of a polyalkylene ether glycol with an epoxide or glycidyl ether each containing free hydroxyl groups or by reaction of the polyalkylene ether glycol with an epoxy compound containing a halogen atom with subsequent replacement of the halogen atom by a hydroxy group.  The modified polyalkylene ether glycol may be first reacted with the polyisocyanate the resulting product then being reacted with water. The polyalkylene ether glycols may be those obtained by condensing an alkylene oxide having 2 to 5 carbon atoms, by the reaction of such alkylene oxides with polyvalent alcohols such as 1, 4-butylene glycol, glycerol, trimethylol propane or pentaerythritol or by polymerisation of tetrahydrofuran.  Modification of these glycols may be effected by reaction (preferably at 30 DEG -130 DEG C. in the presence of catalysts such as boron fluoride etherate or perchloric acid) with such epoxides as the 1, 2-epoxide of glycerol, pentaerythritol monoepoxide, or the oxide of trimethylol propane; or with glycidyl ethers having free hydroxyl groups such as those obtained by reacting a polyhydric alcohol (e.g. glycol, diethylene glycol, glycerol, hexanetriol or trimethylol propane) with epichlorhydrin in such amount that not all the OH groups are etherified.  Another method is to react the polyglycol with epichlorhydrin to give a product containing hydroxyl and chlorine atoms and replacing the chlorine by hydroxyl by boiling with an alkali.  Suitable polyisocyanates are listed.  Tertiary amines and organic compounds are suitable catalysts.  Sulphonated hydrocarbons or castor oil, fillers, dyes and silicone oil are other suitable additives.  In Examples (1) an adduct prepared by reacting a linear polypropylene glycol (M. Wt. 2000) with 2 mols of glycerine -1, 2-oxide in the presence of BF3 etherate is reacted with toluylene diisocyanate. p  The product is foamed by adding a mixture of dimethyl benzylamine, paraffin oil and water; (2) an adduct prepared by the reaction of the polypropylene glycol with 2 mols of epichlorhydrin and saponification of -CH2Cl groups in the product to -CH2OH groups, is reacted with toluylene diisocyanate.  Conversion to a foam material is effected by adding diethylene triamine, silicone oil and water.  Specifications 769,680 and 769,682 are referred to.