The mechanical property and phase structures of wheat proteins/polyvinyl alcohol blends studied by high-resolution solid-state NMR
The mechanical property and phase structures of wheat proteins/polyvinyl alcohol blends studied by high-resolution solid-state NMR
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DOI：
10.1016/j.polymer.2004.02.044
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发表时间：
2004-05
期刊：
影响因子：
4.6
通讯作者：
Xiao-qing Zhang;I. Burgar;E. Lourbakos;H. Beh
中科院分区：
文献类型：
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作者：
Xiao-qing Zhang;I. Burgar;E. Lourbakos;H. Beh
采用固态高分辨率核磁共振波谱技术研究了热处理小麦蛋白（WP）与聚乙烯醇（PVOH）共混物的相结构。在纳米尺度上考察了多组分体系的分子间相互作用和各组分在共混体系中的行为。对共混物的力学性能进行了测试，并对其相结构进行了研究。结果表明，在以甘油和水作为增塑剂的情况下，WP的聚合物链可以被均匀地调动，但在共混物中，甘油主要与WP结合，而PVOH的作用较小。当PVOH含量较低时，WP与PVOH之间的分子间氢键相互作用导致体系在纳米尺度上存在一定程度的混相。与WP相比，共混物的拉伸强度和模量得到了提高。然而，分子间相互作用相对较弱，不能通过增加共混物中PVOH的含量来进一步增强。颗粒可混相WP/PVOH共混物包含塑化WP和PVOH相以及可混相WP/PVOH相。增加共混物中PVOH的含量并不会增加共混物的混相百分率，共混物倾向于不混相，但随着共混物中PVOH含量的增加，共混物的伸长率降低。
The phase structures of thermally processed wheat proteins (WP) and polyvinyl alcohol (PVOH) blends were studied by solid-state high-resolution NMR spectroscopy. The intermolecular interactions among the multi-component systems and the behavior of each component in the blends on scales of nanometers were examined. The mechanical properties of the blends were also measured and related to the phase structure studies. The results indicated that the polymer chains of WP could be homogeneously mobilized when thermally processed with glycerol and water as plasticisers, but the glycerol predominately associated with WP rather than PVOH in the blends. The intermolecular hydrogen bonding interactions between WP and PVOH caused some extent of miscibility in the system on scales of nanometers especially when the PVOH content was low. The tensile strength and modulus of the blends were improved as compared to WP. However, the intermolecular interactions were relatively weak and could not be further enhanced by increasing PVOH component in the blends. The particle miscible WP/PVOH blends contained plasticised WP and PVOH phases in conjunction with the miscible WP/PVOH phase. Increasing the PVOH content in the blends did not result in an increase of the percentage of the miscible phase and the blends tented to be immiscible while the elongation of the blends was reduced when increasing the PVOH content in the blends.