Blends of polycaprolactone with polyvinylalcohol:: a DSC, optical microscopy and solid state NMR study
Blends of polycaprolactone with polyvinylalcohol:: a DSC, optical microscopy and solid state NMR study
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DOI：
10.1016/s0032-3861(98)00253-5
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发表时间：
1999-04-01
期刊：
影响因子：
4.6
通讯作者：
David, C
中科院分区：
文献类型：
--
作者：
De Kesel, C;Lefèvre, C;David, C
聚己内酯（PCL）和聚乙烯醇（PVAl）的共混膜通过蒸发两种组分的六氟异丙醇溶液而获得。共混物无定形部分中聚合物的混溶性已通过传统方法（光学显微镜、DSC 和 FTIR）和固态 NMR 进行了研究。在熔体中观察到相分离。 Tm 没有任何降低，并且存在一个接近纯 PCL 的低温 Tg，支持了共混物非晶部分中相分离的假设。然而，各种实验数据表明组件之间存在某种类型的物理相互作用。这些数据是：共混物中 PCL 结晶度的显着降低、在 45℃ 结晶后 PCL 球晶的形态以及在 50℃ 退火共混物时不存在 PCL 微晶重排成球晶的情况（如在纯 PCL 中观察到的）。使用交叉偏振ha通过固态NMR测量质子自旋晶格弛豫时间T-1，表明这些组分在60-90 nm的尺度上是相容的，因此彼此非常精细地分散。 (C) 1999 Elsevier Science Ltd. 保留所有权利。
Blend films of polycaprolactone (PCL) and polyvinylalcohol (PVAl) have been obtained by evaporation of a solution of both components in hexafluoroisopropanol. The miscibility of the polymers in the amorphous part of the blend has been studied by conventional methods (optical microscopy. DSC and FTIR) and by solid state NMR. Phase separation is observed in the melt. The absence of any lowering of Tm and the presence of one low temperature Tg near that of pure PCL support the hypothesis of phase separation in the amorphous part of the blend. However, various experimental data suggest the presence of some type of physical interactions between components. These data are: the important decrease of PCL crystallinity in the blend, the morphology of PCL spherulites after crystallization at 45 degrees C and the absence upon annealing the blend at 50 degrees C, of any rearrangement of PCL crystallites into spherulites as observed in pure PCL. The measurement of proton spin-lattice relaxation time T-1 by solid state NMR using cross polarization ha, shown that the components are compatible at the scale of 60-90 nm and are thus very finely dispersed into each other. (C) 1999 Elsevier Science Ltd. All rights reserved.