Styrene → Styrene

Participants

Reaction Steps

Poly(styrene [50 mol %], benzyl hydrogen maleate [50 mol %]) was prepared by stirring at reflux for 25 hours a mixture of poly(styrene [50 mol %], maleic anhydride [50 mol %]), 200 mL of benzyl alcohol and 400 mL of THF. The THF was removed on a rotary evaporator, and the product was precipitated in hexane followed by precipitation from THF with diethyl ether to give 46 g of poly(styrene, benzyl hydrogen maleate). A mixture of 25 g of poly(styrene, benzyl hydrogen maleate), 150 mL of 3,4-dihydro-2H-pyran, and 0.5 g of pyridine hydrochloride was stirred at reflux 18 hours. THF was added to reduce the viscosity, and the mixture was stirred 1 hour with crosslinked poly(dimethylaminomethylstyrene). After filtration, the product was precipitated from the filtrate in methanol to give 29 g of poly(styrene, benzyl maleate, tetrahydropyranyl maleate). 1H HMR (360 MHz) shows the molar ratio of tetrahydropyranyl groups (δ 5.8 ppm) to benzyloxy groups (δ 5.0 ppm) to be about 4.4:1. Titration with 0.1N sodium hydroxide shows 0.09 meq/g of COOH groups. DSC: decomposition endotherm 140.75° C. TGA: 24.7% weight loss at 147.9° C.

Provenance & Evidence