Initiating systems for nitroxide-mediated ''living'' free radical polymerizations: Synthesis and evaluation

被引：359

作者：

Hawker, CJ ^{[1
]}

Barclay, GG ^{[1
]}

Orellana, A ^{[1
]}

Dao, J ^{[1
]}

Devonport, W ^{[1
]}

机构：

[1] SHIPLEY CO INC,MARLBOROUGH,MA 01752

来源：

MACROMOLECULES | 1996年 / 29卷 / 16期

关键词：

D O I：

10.1021/ma951905d

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

A variety of initiating systems for the preparation of macromolecules by nitroxide-mediated ''living'' free radical procedures have been prepared and evaluated. The systems can be divided into two classes, unimolecular initiators in which alkylated TEMPO (2,2,6,6-tetramethylpiperidinyloxy) derivatives dissociate to provide both the initiating radical and the stable radical, and bimolecular systems in which a traditional free radical initiator, such as BPO or AIBN, is used in conjunction with TEMPO. For the unimolecular initiators it was found that an alpha-methyl group is essential for ''living'' character, while a variety of substituents could be placed on the phenyl ring or the beta-carbon atom without affecting the efficiency of the unimolecular initiator. It was also found that the rate of polymerization is approximately the same for both the unimolecular and corresponding bimolecular systems; however, the unimolecular initiators afforded better control over molecular weight and polydispersity.

引用

页码：5245 / 5254

页数：10

共 44 条

[1] THE MEASUREMENT OF THE ONE-FOLD ROTATIONAL BARRIER OF ECLIPSED BONDS - A DYNAMIC NMR DETERMINATION OF N-O OR N-CH2 BOND ROTATION IN N-ALKOXY-2,2,6,6-TETRAMETHYLPIPERIDINES OR N-ALKYL-2,2,6,6-TETRAMETHYLPIPERIDINES [J].