ORIENTATION KINETICS OF THERMOTROPIC MAIN-CHAIN LIQUID-CRYSTALLINE POLYMERS IN A MAGNETIC-FIELD

被引:45
作者
ANWER, A [1 ]
WINDLE, AH [1 ]
机构
[1] UNIV CAMBRIDGE,DEPT MAT SCI & MET,PEMBROKE ST,CAMBRIDGE CB2 3QZ,ENGLAND
关键词
LIQUID-CRYSTALLINE POLYMER; THERMOTROPIC; MAGNETIC FIELDS; ORIENTATION;
D O I
10.1016/0032-3861(91)90569-5
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
This work presents a quantitative analysis of the kinetics of orientation of main-chain thermotropic liquid-crystalline copolyesters in a magnetic field. Preferred chain orientation has been induced in samples with weight-average molecular weight up to 14 400. The kinetics of the orientation process have been explored as a function of the time in the field, sample temperature and field strength (up to 1.12 T), and in particular the influence of molecular weight has also been determined. It has proved possible to achieve a degree of preferred orientation up to < P2 > = 0.90. Curve fitting the data leads to the determination of maximum < P2 > values and characteristic time constants.
引用
收藏
页码:103 / 108
页数:6
相关论文
共 17 条
  • [1] DOMAIN FORMATION IN THIN-FILMS OF A THERMOTROPIC COPOLYMER
    ANWER, A
    SPONTAK, RJ
    WINDLE, AH
    [J]. JOURNAL OF MATERIALS SCIENCE LETTERS, 1990, 9 (08) : 935 - 936
  • [2] THE RECENT DEVELOPMENTS OF THERMOTROPIC LIQUID-CRYSTALLINE POLYMERS
    CHUNG, TS
    [J]. POLYMER ENGINEERING AND SCIENCE, 1986, 26 (13) : 901 - 919
  • [3] DEGENNES PG, 1974, PHYSICS LIQUID CRYST
  • [4] MAGNETIC EFFECTS AND VISCOSITY IN THE NEMATIC PHASE OF A POLYMER SERIES
    HARDOUIN, F
    ACHARD, MF
    GASPAROUX, H
    LIEBERT, L
    STRZELECKI, L
    [J]. JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS, 1982, 20 (06) : 975 - 980
  • [5] HERLACH F, 1985, TOPICS APPLIED PHYSI, V57
  • [6] KOZAK A, 1989, POLYM COMMUN, V30, P102
  • [7] KRIGBAUM WR, 1982, POLYM LIQUID CRYSTAL, P275
  • [8] LEMMON TJ, 1989, THESIS U CAMBRIDGE
  • [9] ORIENTATION OF THERMOTROPIC LIQUID-CRYSTALLINE POLYESTERS IN HIGH MAGNETIC-FIELDS
    MARET, G
    BLUMSTEIN, A
    [J]. MOLECULAR CRYSTALS AND LIQUID CRYSTALS, 1982, 88 (1-4): : 295 - 309
  • [10] MEASUREMENT OF THE VISCOELASTIC COEFFICIENTS OF MAIN-CHAIN NEMATIC POLYMERS BY AN NMR TECHNIQUE
    MARTINS, AF
    ESNAULT, P
    VOLINO, F
    [J]. PHYSICAL REVIEW LETTERS, 1986, 57 (14) : 1745 - 1748