RELAXATION PROCESSES IN THERMOTROPIC POLYDIBENZOATES WITH OXYETHYLENE SPACERS IN THE MAIN-CHAIN

被引：28

作者：

BENAVENTE, R ^{[1
]}

PERENA, JM ^{[1
]}

PEREZ, E ^{[1
]}

BELLO, A ^{[1
]}

机构：

[1] CSIC,INST CIENCIA & TECNOL POLIMEROS,JUAN CIERVA 3,E-28006 MADRID,SPAIN

来源：

POLYMER | 1993年 / 34卷 / 11期

关键词：

DYNAMIC MECHANICAL RELAXATIONS; THERMOTROPIC POLYDIBENZOATES; MAIN-CHAIN LIQUID-CRYSTALLINE POLYMERS; OXYETHYLENE SPACERS;

D O I：

10.1016/0032-3861(93)90818-U

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 dynamic mechanical analysis has been performed on three thermotropic polydibenzoates, designated PDEB, PTEB and PTTB, synthesized from p,p'-dibenzoic acid and di-, tri- or tetraethylene glycol, respectively. The isotropization temperature decreases greatly as the length of the spacer increases, and the mesophase of PTTB is not detected at all. Three dynamic mechanical relaxations are found for each polymer in the temperature range from -150 to 100-degrees-C. The ot relaxation corresponds to the glass transition of the polydibenzoates, the beta relaxation is typical of polyesters and the gamma relaxation has its origins in the crankshaft motions of the oxyethylene units in the spacer, i.e. the oxygen atom can cooperate in this movement when substituting for a methylenic unit.

引用

页码：2344 / 2347

页数：4

共 18 条

[11] THERMOTROPIC HOMOPOLYESTERS .5. INVESTIGATION OF THE SMECTIC PHASE OF POLYESTERS BASED ON PARA,PARA'-BIBENZOIC ACID [J].

KRIGBAUM, WR ;

WATANABE, J .

POLYMER, 1983, 24 (10) :1299-1307

[12]

Meurisse P., 1981, British Polymer Journal, V13, P55, DOI 10.1002/pi.4980130204

[13]

PERENA JM, 1991, J NONCRYST SOLIDS, V131, P893

[14] SOLUBILITY OF THERMOTROPIC POLYBIBENZOATES WITH OXYETHYLENE SPACERS [J].

PEREZ, E ;

BENAVENTE, R ;

MARUGAN, MM ;

BELLO, A ;

PERENA, JM .

POLYMER BULLETIN, 1991, 25 (03) :413-418

[15] THERMOTROPIC PROPERTIES AND CONFORMATIONAL STUDIES ON POLY(TRIETHYLENE GLYCOL PARA,PARA'-BIBENZOATE) AND POLY(OCTAMETHYLENE PARA,PARA'-BIBENZOATE) [J].

PEREZ, E ;

RIANDE, E ;

BELLO, A ;

BENAVENTE, R ;

PERENA, JM .

MACROMOLECULES, 1992, 25 (02) :605-610

[16]

PEREZ E, 1990, POLYM COMMUN, V31, P386

[17] THERMOTROPIC LIQUID-CRYSTALS OF POLYESTERS HAVING A MESOGENIC PARA,PARA'-BIBENZOATE UNIT .1. SMECTIC MESOPHASE PROPERTIES OF POLYESTERS COMPOSED OF PARA,PARA'-BIBENZOIC ACID AND ALKYLENE GLYCOLS [J].

WATANABE, J ;

HAYASHI, M .

MACROMOLECULES, 1988, 21 (01) :278-280

[18]

WUNDERLICH B, 1984, ADV POLYM SCI, V60-1, P1

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