PROPERTIES OF POLY-BETA-HYDROXYBUTYRATE .1. GENERAL CONSIDERATIONS CONCERNING THE NATURALLY OCCURRING POLYMER
PROPERTIES OF POLY-BETA-HYDROXYBUTYRATE .1. GENERAL CONSIDERATIONS CONCERNING THE NATURALLY OCCURRING POLYMER
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DOI：
10.1002/bip.360010605
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发表时间：
1963-01-01
期刊：
影响因子：
2.9
通讯作者：
COTE, WA
中科院分区：
文献类型：
--
作者：
ALPER, R;LUNDGREN, DG;COTE, WA
已通过两种不同的方法从两种细菌来源中分离出聚β-羟基丁酸。两种样品的分子量和特性粘度有很大的不同。这归因于聚合物分离期间发生的降解。高分子量样品的旋光色散曲线表明，在小于450 m μ的波长处，比旋光度急剧增加。根据这一事实和单体的旋光活性，可以得出结论，聚合物是立体规整的。“天然”和“再生”聚合物的X射线检查产生相同的结晶图案。聚合物单晶的电子衍射和X射线数据表明纤维重复为5.9 A。该值只能与固态中的某种螺旋构象相一致。
Poly‐β‐hydroxybutyric acid has been isolated from two bacterial sources by two different procedures. Molecular weight and intrinsic viscosity for the two samples were vastly different. This was blamed on degradation occurring during polymer isolation. An optical rotatory dispersion curve for the high molecular weight sample showed a sharp increase in specific rotation at wavelengths less than 450mμ. From this fact and the reported optical activity of the monomer it is concluded that the polymer is stereo‐regular. X‐ray examination of the “native” and “regenerated” polymer yielded the same crystalline pattern. Electron diffraction and x‐ray data on single crystals of the polymer indicate a fiber repeat of 5.9 A. The value can only be reconciled with some kind of helical conformation in the solid state.