SYNTHESIS AND PROPERTIES OF LIQUID-CRYSTALLINE POLYURETHANES

被引:85
作者
PENCZEK, P [1 ]
FRISCH, KC [1 ]
SZCZEPANIAK, B [1 ]
RUDNIK, E [1 ]
机构
[1] UNIV DETROIT,POLYMER TECHNOL INC,DETROIT,MI 48221
关键词
MAIN-CHAIN LIQUID CRYSTALLINE POLYMERS; THERMOTROPIC; POLYURETHANES; SYNTHESIS; CHARACTERIZATION;
D O I
10.1002/pola.1993.080310517
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
Liquid crystalline polyurethanes were prepared from 4,4'-bis(2-hydroxyethoxy)biphenyl (BHBP) and 2,4-tolylene diisocyanate (TDI). The effect of partial replacement of BHBP by 25-75 mol % poly (oxytetramethylene) diol (PTMO, M(n)BAR = 250) on the liquid crystalline properties was studied. The BHBP / TDI / PTMO polyurethanes were obtained by one- and two-step polyaddition. The polyurethanes were investigated by DSC, polarizing microscopy, x-ray, and IR spectroscopy. The molecular weight distribution was determined by GPC. The morphology of the polymers was investigated by the SALS method. Thermogravimetric investigations of the polyurethanes were also performed. All polyurethanes containing BHBP units have liquid crystalline properties. Partial replacement of BHBP by PTMO-250 considerably changes the phase transition temperatures and the range of mesophase occurrence. More homogeneous polyurethanes were obtained, if the two-step polyaddition method was a lied. The polyaddition method affects the phase transition temperatures.
引用
收藏
页码:1211 / 1220
页数:10
相关论文
共 19 条
[1]  
DICKE HR, 1983, J POLYM SCI POL CHEM, V21, P258
[2]  
HSU CS, 1987, MAKROMOL CHEM, V188, P1017
[3]  
IIMURA K, 1981, MAKROMOL CHEM, V182, P2563
[4]  
IIMURA K, 1981, MAKROMOL CHEM, V182, P2569
[5]  
JEDLINSKI Z, 1986, MAKROMOL CHEM, V187, P2317
[6]   NEMATOGENIC POLYMERS HAVING RIGID CHAINS .1. SUBSTITUTED POLY(PARA-PHENYLENE TEREPHTHALATES) [J].
KRIGBAUM, WR ;
HAKEMI, H ;
KOTEK, R .
MACROMOLECULES, 1985, 18 (05) :965-973
[7]  
KRIGBAUM WR, 1987, J POLYM SCI POL CHEM, V25, P652
[8]   THERMAL AND MECHANICAL-PROPERTIES OF POLYURETHANES WITH MESOGENIC DIOL COMPONENTS [J].
LORENZ, R ;
ELS, M ;
HAULENA, F ;
SCHMITZ, A ;
LORENZ, O .
ANGEWANDTE MAKROMOLEKULARE CHEMIE, 1990, 180 :51-71
[9]   LIQUID-CRYSTAL POLYMERS .11. STRUCTURE PROPERTY RELATIONSHIPS IN A SERIES OF THERMOTROPIC POLY(2-NORMAL-ALKYL-1,4-PHENYLENE TEREPHTHALATES) [J].
MAJNUSZ, J ;
CATALA, JM ;
LENZ, RW .
EUROPEAN POLYMER JOURNAL, 1983, 19 (10-1) :1043-1046
[10]   A THERMODYNAMIC INTERPRETATION OF POLYMER MOLECULAR-WEIGHT EFFECT ON THE PHASE-TRANSITIONS OF MAIN-CHAIN AND SIDE-CHAIN LIQUID-CRYSTAL POLYMERS [J].
PERCEC, V ;
KELLER, A .
MACROMOLECULES, 1990, 23 (20) :4347-4350