Hydrogenated ring-opened polynorbornene: A highly crystalline atactic polymer
Hydrogenated ring-opened polynorbornene: A highly crystalline atactic polymer
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DOI：
10.1021/ma048013a
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发表时间：
2005-02-22
期刊：
影响因子：
5.5
通讯作者：
Register, RA
中科院分区：
文献类型：
--
作者：
Lee, LBW;Register, RA
用大多数催化剂进行的异戊二烯的开环易位聚合（ROMP）产生具有亚环戊基环的无规放置的聚合物，然而已知该聚合物的部分氢化产生结晶产物。我们在这里报告一个简单的催化路线饱和聚异丁烯（PN），完全氢化聚异丁烯（hPN）是高度结晶，与平衡熔点估计为156 degreesC。晶格为单斜晶系，室温下参数a = 6.936埃，B = 9.596埃，c = 12.420埃，β = 130.7度，表明hPN骨架在晶胞内几乎完全延伸。该材料在达到熔点之前保持高度结晶，但在接近105 ℃时，晶体结构转变为以hPN链围绕其轴的实质性旋转无序为特征的晶体结构，同时保持实质性平移有序。
Ring-opening metathesis polymerization (ROMP) of norbornene with most catalysts produces a polymer with an atactic placement of the cyclopentylene rings, yet partial hydrogenation of this polymer is known to yield a crystalline product. We report here a facile catalytic route to saturate polynorbornene (PN); fully hydrogenated polynorbornene (hPN) is highly crystalline, with an equilibrium melting point estimated as 156degreesC. The crystal lattice is monoclinic, with parameters a = 6.936 Angstrom, b = 9.596 Angstrom, c = 12.420 Angstrom, and beta = 130.7degrees at room temperature, indicating nearly complete extension of the hPN backbone within the unit cell. The material remains highly crystalline until the melting point is reached, but near 105degreesC, the crystal structure transforms to one characterized by substantial rotational disorder of the hPN chains about their axes, while retaining substantial translational order.