Patent GB-819020-A (GB)
Title: Improvements in or relating to polymeric materials
IPC: C08F8/00
Filed: 1956-08-16
Abstract: Linear polymers which cross-link when heated to 100-325 DEG  C consist of repeating units of which at least 1 per cent have an extralineal substituent containing a cyclobutene ring linked to the polymer chain through a nitrogen or an oxygen atom, the carbon atoms of the cyclobutene ring carrying at least two hydrogen atoms and any halogen substituents on said ring being on unsaturated carbon atoms. They are made by reacting at below 150 DEG  C., a preformed polymer containing a plurality of amino or hydroxyl groups with a reactant containing a cyclobutene ring which preferably has the formula <FORM:0819020/IV (a)/1> where R is a substituent attached to the 1, 2 or 3 position which is reactive with an amino or hydroxyl group, R1 is a hydrogen atom, a lower alkyl group, a carboxyl group, a group hydrolysable to carboxyl, an amino group or a halogen atom and R11 is a hydrogen atom, a lower alkyl group or a divalent saturated aliphatic radical forming with R and two adjacent carbon atoms of the cyclobutene ring a 5- or 6-membered aliphatic ring. The polymers may be used in the manufacture of shaped articles, printing inks, finishes, adhesives, films and fibres, cross-linking of such materials being subsequently effected. Examples describe polymers obtained by reacting (1) poly-p-amino-styrene and 2-bromo-1-cyclobutene-1-carboxylic acid chloride; (2) and (3) a polymer obtained by reductive amination of an ethylene/carbon monoxide polymer (see Specification 652,566) and 2-bromo-1-cyclobutene-1-carboxylic acid chloride, and 1- or 3 - methyl - 1 - cyclobutene - 1 - carboxylic acid chloride; (4) polyvinyl alcohol or cellulose and 1 - methyl - 1 - cyclobutene - 2,3 - dicarboxylic acid chloride.ALSO:The Specification describes the preparation of the following compounds containing a cyclobutene ring which are used for reaction with polymers (see Group IV (a)).  (1) Bis-cyclooctaene carboxylic acid chloride obtained by condensing 1,2 - dimethylene - cyclobutane with acrylic acid and converting to the acid chloride with thionyl chloride; (2) 2-bromo-1-cyclobutene - 1 - carboxylic acid chloride obtained by heating the corresponding acid with thionyl chloride; (3) 3-methyl-1-cyclobutenecarboxylic acid chloride obtained from 1 - methyl - 3 - cyclobutanecarbonitrile by addition of hydrogen iodide, hydrolysis with aqueous alkali, neutralization with hydrochloric acid and treatment of the resulting carboxylic acid with thionyl chloride; (4) 1-methyl - 1 - cyclobutene - 3 - carboxylic acid chloride obtained from methyl-3-methylene-1-cyclobutene-1-carboxylate by reacting it with hydrogen iodide followed by elimination of hydrogen iodide with a tertiary amine to form 3 - carbomethoxy - 1 - methylcyclobutene, addition of bromine to which gives 1,2-dibromo-3 - carbomethoxy - 1 - methylcyclobutane which is then hydrolysed and the free acid treated with potassium iodide to remove the bromine, and the resulting 1-methyl-1-cyclo-butene-3-carboxylic acid converted to the acid chloride with thionyl chloride.  Specification 652,566 [Group IV (a)], is referred to.