In this work, to characterize the mobility of different sections of the macromolecules of polyurethane (PUR), polyvinyl alcohol (PVA), and polylactic acid (PLA), as well as the density of crosslinks of the polymer chains when using fillers, we used the distributions of spin–lattice and spin–spin relaxation times for the protons. It is shown that the rigidity of the thermoplastic polymers depends on the sizes of the granules of the diatomite filler, which can embed in the polymer matrix. Consequently, relaxation times are reduced. If PLA is the filler of PUR, the dynamics of the molecules in the chains and the spin–spin interaction of the protons are affected by the crosslinking of PUR by PLA. An increase in crosslinks density reduces the rate of polymer degradation.

中文翻译：

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PVA、PLA或硅藻土填充热塑性医用聚氨酯对1H NMR弛豫时间分布影响的研究

在这项工作中，为了表征聚氨酯 (PUR)、聚乙烯醇 (PVA) 和聚乳酸 (PLA) 大分子不同部分的流动性，以及使用填料时聚合物链的交联密度，我们使用质子的自旋-晶格和自旋-自旋弛豫时间的分布。结果表明，热塑性聚合物的刚度取决于硅藻土填料颗粒的尺寸，硅藻土填料可以嵌入聚合物基质中。因此，弛豫时间减少。如果 PLA 是 PUR 的填料，则链中分子的动力学和质子的自旋-自旋相互作用受 PLA 交联 PUR 的影响。交联密度的增加降低了聚合物降解的速率。