Multiphase materials with lignin: 13. Block copolymers with cellulose propionate
Multiphase materials with lignin: 13. Block copolymers with cellulose propionate
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含有木质素的多相材料： 13. 与丙酸纤维素的嵌段共聚物
DOI：
10.1016/0032-3861(94)90991-1
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发表时间：
1994
期刊：
影响因子：
4.6
通讯作者：
W. Glasser
中科院分区：
文献类型：
--
作者：
W. D. Oliveira;W. Glasser
用上述化学方法合成了由橡胶木素衍生物组分(即羟丙基木质素，L)和聚合度(DP)5~60的纤维素丙酸酯(CP)链段组成的嵌段共聚物。嵌段共聚物(LCP)的结构和组成的大小不同。用溶液、热和光学等方法对共聚物进行了表征，并通过力学性能测试确定了共聚物对L/CP共混物性能的影响。结果表明，共聚物物性主要由CP链段大小决定。具有较短CP链段的共聚物表现为球形大分子，而具有较大CP链段的共聚物具有棒状行为。所有嵌段共聚物都显示出Tm值，即使CP臂长度低至5。DP60的CP链的结晶度最高。共聚物的形态各不相同；它们显示出类似于分散的纤维、球状和交替的片层类型的图案，这取决于组成和链段几何形状。嵌段共聚物对L/CP共混体系的性能影响很小。这归因于木素衍生物与CP的整体相容性。
Block copolymers consisting of rubbery lignin derivative components (i.e. hydroxypropyl lignin, L) and cellulose propionate (CP) segments ranging in size from degree of polymerization (DP) 5 to 60 were synthesized using chemistry described previously. The block copolymers (LCP) varied in relation to architecture and size of component. The copolymers were characterized by solution, thermal and optical techniques, and their effect on the properties of L/CP blends was determined by mechanical tests. The results suggest that copolymer properties are dictated primarily by CP segment size. Whereas copolymers with short CP segments behaved like spherical macromolecules, copolymers with large CP segments had rod-like behaviour. All block copolymers displayedTmvalues, even if CP arm length was as low as 5. Crystallinity was highest at CP chains ofDP60. Copolymer morphologies varied; they revealed patterns resembling dispersed fibrils, spheres and alternating lamella types depending on composition and segment geometries. The block copolymers had surprisingly little effect on L/CP blend properties. This was attributed to the overall- compatibility of lignin derivatives with CP.