SYNTHESIS AND MESOMORPHIC PROPERTIES OF FISHBONE-LIKE LIQUID CRYSTALLINE POLYSILSESQUIOXANES——Ⅰ. FISHBONE-LIKE, β-DIKETONE-BASED LIQUID CRYSTALLINE POLYSILSESQUIOXANES AND THEIR COPPER COMPLEXES*

Two kinds of fishbone-like, β-diketone-based liquid crystalline polysilsesquioxanes(FBDKLCP'S), homopolymeric (H-FBDKLCP) and copolymeric (C-FBDKaLCP) have been first synthesized via the hydrosilylation reaction of a vinyl-terminated β-diketone with the homopolymeric ladderlike polyhydrosilsesquioxane (LPHSQ) and random copolymethylhydrosilsesquioxane (LRPMHSQ) respectively. These new kinds of FBDKLCP with M of 10~4 is thermotroic liquid crystalline polymer and its clearing temperatures T_i's and mesophase range △T's are much higher than those of the corresponding comb-like β-diketone liquid crystalline polysiloxane (DKLCP) by about 200℃. Similar results have been observed with the comparison of the two different structure Cu-coordinating compounds The significant increases in T_((?))'s and △T's of the FBDKLCP and Cu-FBDKLCP are mainly attributed to the great rigidity of the ladderlike polysilsesquioxane backbone.     

INTERACTION BETWEEN ISOTACTIC POLYPROPYLENE AND ITS NON-SOLVENTS

Polypropylene (PP) microporous film prepared by biaxial stretching of isotactic PPis treated with non-solvent liquid at room temperature. The dimension of the film maychange after the treatment. The degree of area contraction of PP film is dependent on thematch between PP and liquid in solubility parameter and polarity. The fact indicates thatsome interactions do exist between liquid and isotactic PP, and a shrinkable porous film isa sensitive probe to detect the weak interactions.     

MELTING AND CRYSTALLIZATION BEHAVIOR OFAN AROMATIC POLY (AZOMETHINE ETHER) WITH NON-LINEARLY SHAPED MOLECULAR CONFORMATIONS

The melting and crystallization behavior have been investigated for an aromatic poly(azomethine ether) with non-linearly shaped molecular conformations. This polymer wasfound to undergo multiple melting processes and its phase transition behavior wasinfluenced sensitively by the thermal history of sample. A significant difference between thepolymer chain aggregation abilities of samples cooled from the different states wasobserved. The possible molecular morphology and aggregation models for describing thestructures of this polymer were proposed and discussed. The crystallization behavior of thesamples cooled from the partially isotropic state and the influence of cooling rate on it havealso been examined with DSC.     

光致变色液晶高分子研究（Ⅲ）──含胆甾介晶基元和偶氮苯光色基元侧链共聚硅氧烷的液晶行为

用热台偏光显微镜、Ｘ射线衍射和ＤＳＣ研究了含胆甾介晶基元和偶氮苯光色基元侧链共聚硅氧烷（ＰＳＩ）的液晶性．将非介晶基元并入液晶均聚物，所得共聚物的液晶态类型不变，仍显示近晶型织构，在ＰＳＩ共聚物中，保持液晶性的含介晶基元单体的最低极限组成为６０ｍｏｌ％．在液晶性存在的范围内，共聚物的清亮点由１３０℃升至１７０℃，液晶共聚物的热稳定性随非介晶组分含量的增加而增强．     

光致变色液晶高分子研究（Ⅲ）：含胆甾介晶基元和偶氮苯…

用热台偏光显微镜、Ｘ射线衍射和ＤＳＣ研究了含胆甾介晶基元和偶氮苯光色基元侧链共聚硅氧烷（ＰＳＩ）的液晶性。将非介晶基元并入液晶均聚物，所得共聚物的液晶态类型不变，仍显示近晶型织，在ＰＳＩ共聚物中，保持液晶性的含介晶基元单体的最低极限组成为６０ｍｏｌ％．在液晶性存在的范围内，共聚物的清亮点由１３０℃升至１７０℃，液晶共聚物的热稳定性随非晶组分含量的增加而增强。     

光致变色液晶高分子研究(Ⅳ)─含苯甲酸－4－甲氧基苯酯介晶基元和偶氮苯光色基元侧链共聚硅氧烷的液晶行为

用热台偏光显微镜和DSC法研究了含苯甲酸-4-甲氧基苯酯介晶基元和偶氮苯光色基元侧链共聚硅氧烷(PSⅡ)的液晶性。将非介晶基元并入液晶均聚物PSⅡ-1,共聚物PSⅡ-2、PSⅡ-3的液晶态类型不变,PSⅡ-4仅存在近晶相,PSⅡ-5～8无双折射现象,保持共聚物液晶性的最低含介晶基元单体的极限摩尔含量为80%.在液晶共聚物中,非介晶基组分含量增加时,其T_m、ΔH_m和ΔS_m降低;非介晶组分在10mol%时,T_i、ΔH_i和ΔS_i具有最小值。