ISSN:
1436-2449
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Summary The synthesis of α,ω-di-tert—chloropolyisobutylenes(chlorinetelechelic PIB's) have been accomplished at −30°C by the use of “sterically hindered inifers”. A suitable sterically hindered binifer is 1,3-di(2-chloro-2-propyl)-5-tert -butylbenzene, m-tBuDCC, i.e., a binifer in which the bulky tert-butyl group prevents undesirable intramolecular alkylation with concomitant proton elimination. Conventional binifers i.e., 1,4-di(2-chloro-2-propyl)benzene (p-dicumyl chloride, pDCC) give rise to this unacceptable side reaction unless the inifer process is carried out at −80°. The use of m-tBuDCC leads to satisfactory telechelic PIB's with number average end functionalities (¯Fn) of 2.0±0.1. The ¯fn and ¯Mn of the products are unaffected by temperature in the −30 to −80°C range. In the absence of the bulky tert-butyl group in the inifer, i.e., with 1,3-di(2-chloro-2-propyl)benzene, mDCC, severe indanyl ring formation occurs.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00255350
Permalink
