The relationship between blend miscibility and biodegradation of cellulose acetate and poly(ethylene Succmate) blends
The relationship between blend miscibility and biodegradation of cellulose acetate and poly(ethylene Succmate) blends
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醋酸纤维素与聚琥珀酸乙二醇酯共混物的混溶性与生物降解性的关系
DOI：
10.1007/bf02763665
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
M. Wood
中科院分区：
文献类型：
--
作者：
C. Buchanan;Barry Glen Pearcy;A. White;M. Wood
采用多种热技术和固态碳13核磁共振波谱法研究了醋酸纤维素（CA；取代度= 2.5）与聚琥珀酸乙烯酯（PES）的混溶性。发现ca含量大于70%的共混物是可混溶的。对于ca含量低于70%的共混物，热分析和核磁共振分析的结合表明，这些共混物在2.5至5纳米尺度上不能完全混溶。在可通过动态机械热分析（15 nm）探测的尺度上，低百分比CA共混物表现出“显著的局部浓度波动≓”。对共混物组分和共混物的生物降解研究表明，PES降解相对较快，CA降解较慢。共混物的降解速率与CA基本相同。混相（75% CA共混物）或聚醚砜（30% CA共混物）的结晶性没有显著影响。这些数据表明，降解的一个重要模式ófPESduring堆肥涉及化学水解的聚合物，其次是单体的生物同化。共混物的降解始于非晶相。由于CA是非晶相的重要组成部分，少量的CA会显著影响共混物的生物降解率。
The miscibility of cellulose acetate (CA; degree of substitution = 2.5) and poly(ethylene succinate) (PES) has been investigated using a variety of thermal techniques and by solid-state carbon13 NMR spectroscopy. The blends containing greater than ca. 70% CA were found to be miscible. In the case of blends containing less than ca. 70% CA, a combination of thermal and NMR analyses suggests that these blends are not fully miscible on a 2.5- to 5-nm scale. On the scale which can be probed by dynamic mechanical thermal analysis (15 nm), the low-percentage CA blends exhibit “significant local concentration fluctuations≓. Investigation of the biodegradation of the blend components and of the blends revealed that PES degraded relatively rapidly and that CA degraded slowly. The blends degraded at a rate essentially identical to that of CA. Miscibility (75% CA blend) or crystallization of PES (30% CA blend) had no significant effect. These data suggest that a significant mode of degradation ófPESduring composting involves chemical hydrolysis of the polymer followed by biological assimilation of monomers. Degradation of the blends is initiated in the amorphous phase. Because CA is a significant component of the amorphous phase, a small amount of CA significantly impacts the biodegradation rates of the blends.