Effects of preparation temperature on swelling and mechanical properties of PVA cast gels
Effects of preparation temperature on swelling and mechanical properties of PVA cast gels
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DOI：
10.1039/c2sm25513h
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发表时间：
2012-01-01
期刊：
影响因子：
3.4
通讯作者：
Suzuki, Atsushi
中科院分区：
文献类型：
--
作者：
Otsuka, Emiko;Komiya, Shin;Suzuki, Atsushi
在不同凝胶化温度下制备了聚乙烯醇（PVA）铸态凝胶（T-gel），通过平衡重量测定、单轴加载试验、撕裂力测定和室温循环压缩试验对PVA铸态凝胶的溶胀率和力学性能进行了表征。结果表明，随着T-凝胶含量的增加，共混物的溶胀率降低，断裂应力和撕裂能均增加。压缩变形50%的压缩变形能单调增加，而滞后损失不受T-凝胶的影响。为了理解这些宏观性质，通过X射线衍射和傅里叶变换红外测量来检查样品的网络结构。结果，微晶的尺寸随着T-凝胶的增加而增加，并且微晶之间的平均距离也增加。这些结果表明，由微晶交联的PVA网络的结构在决定PVA浇铸凝胶的力学性能方面具有重要作用。的宏观力学性能进行了讨论的基础上的尺寸，数量和分布的微晶作为交联剂和无定形PVA网络，这是确定在凝胶化的均匀性。
Poly(vinyl alcohol) cast gels (PVA cast gels) were prepared at different gelation temperatures, T-gel, and the swelling ratio and mechanical properties were characterized by the equilibrium weight measurement, a uniaxial loading test, a tearing force measurement, and a cyclic compression test at room temperature. The results showed that the swelling ratio decreased and both the breaking stress and the tearing energy increased with an increase in T-gel. The compression deformation energy of 50% reduction of its original size increased monotonically, while the hysteresis loss was not affected by T-gel. To understand these macroscopic properties, the network structures of the samples were examined by X-ray diffraction and Fourier transform infrared measurements. As a result, the size of the microcrystallites increased with an increase in T-gel and the average distance between the microcrystallites also increased. These results suggested that the structures of PVA networks, crosslinked by the microcrystallites, have essential roles in determining the mechanical properties of PVA cast gels. The macroscopic mechanical properties are discussed on the basis of the size, number, and distribution of microcrystallites as crosslinkers and the homogeneity of amorphous PVA networks, which were determined at gelation.