THE NITRATION OF POLYSTYRENE

Four methods for the nitration of polystyrene are compared: (i) direct nitration with a nitric acid/sulfuric acid mixture; (ii) nitration in carbon tetrachloride with acetyl nitrate; (iii) nitration in N,N'-dim ethylformamide with a nitric acid/sulfuric acid mixture; and (iv) nitr ation in 3-nitrotoluene with a nitric acid/sulfuric acid mixture. It i s demonstrated that the first three methods give products with low deg rees of substitution and lead to a broadening of the molecular weight distribution, but that method (iv) gives poly(4-nitrostyrene) with min imal effect on the breadth of the molecular weight distribution. The g lass transition temperature for poly(4-nitrostyrene) is found to appro ach 194.6-degrees-C at high molecular weights.