Technical Paper Archive


This site contains all papers presented at Rubber Division, ACS Technical Meetings from 2000-2018. Meetings prior to 2000 are incomplete and papers are added as they are digitized.


For older papers not listed here, please send your request, including Meeting Year, Title, Author, and Paper # to: cbrady@rubber.org


View Your Rubber Division Account

SYNTHESIS OF HIGH 1,2-NIICROSTRUCTURE OF POLY(1,3- BUTADIENE) USING A BIOBASED LEWIS BASE

43

Event: 182nd Technical Meeting
Location: Cincinnati, OH
Date: October 09, 2012
Author: Roderic Quirk, Hongwei Ma, Shih-Fan Wang
Paper Number: 43

Price: $20.00

  • One of the most unique and important aspects of living alkyllithium- initiated anionic polymerization is the ability to prepare poly(1,3-dienes) and styrene-diene copolymers with high 1,4-microstructure in hydrocarbon solution. [1] These high 1,4-polydienes exhibit low glass transition temperatures and excellent elastomeric properties after crosslinking.[2,3] For example, butyllithium-initiated polymerization of 1,3-butadiene produces a polymer with 91% 1,4-microstructure (55% trans- and 35% cis-) and a glass transition temperature of -90 0C.[1] A important control variable for alkyllithium-initiated polymerization of 1,3-dienes is the ability to increase the amount of 1,2-enchainment by addition of increasing amounts Lewis bases, which systematically increases the glass transition temperature of the polymer.[4,5] Thus, polybutadiene with 9'1"% 1,2-microstructure can be prepared by effecting the polymerization in cyclopentane at 5 BC in the presence of 1 equivalent of 1,2-bispiperidinoethane relative to lithium,[6,'1"] bidentate bases have proven to be most effective for this purpose.[1] However, the practical extension of this procedure to higher temperature results in decreasing amounts of 1,2-microstructure.[8] For example, polybutadiene with only 31% 1,2-microstructure is formed with one equivalent of 1,2-bispiperidinoethane at T0 0C.['1"] Thus, there has been continuing interest in finding Lewis bases that would generate high 1,2- polydiene microstructures while exhibiting less temperature sensitivity with respect to 1,2-diene enchainment in alkyllithium-initiated polymerizations.

    Papers from 182nd Technical Meeting

    Items from 182nd Technical Meeting