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聚氨酯包合物制备刚韧平衡聚甲醛合金

时间:2020-04-25 15:27来源:毕业论文
POM 与弹性体共混是提高POM 韧性的最好方法,而热塑性聚氨酯弹性体(Thermoplastic polyurethanes,TPU)是其中增韧效果最好的改性剂。但是单纯地加入 TPU,在获得高韧性的同时,POM 的强度、

摘要 聚甲醛(Polyoxymethylene,POM)是五大工程塑料之一,具有优异的强度和刚性,但是POM 的韧性低、热稳定性差。将POM 与弹性体共混是提高POM 韧性的最好方法,而热塑性聚氨酯弹性体(Thermoplastic polyurethanes,TPU)是其中增韧效果最好的改性剂。但是单纯地加入 TPU,在获得高韧性的同时,POM 的强度、模量和硬度会大幅下降。 近年来,对于包合物(ICs)改性聚合物的研究受到广泛关注,由于其特殊的“主-客”体结构,使得包合物可以有效提高聚合物的性能。因此我们创新性地制备了 TPU 与β-环糊精(β-CD)的包合物β-CD: TPU=1: 1, 记作 IC-TPU(1-1)。 研究结果表明,共混物 POM/IC-TPU(1-1)表现出优异的性能,在达到预期的刚韧平衡效果同时,也提高了 POM 的热稳定性。进一步发现,使POM 达到这种效果的原因在于包合物特殊的“软壳-硬核”结构:“软壳”提高了POM 的韧性,“硬核”弥补了弹性体增韧造成的强度和模量的损失,并起到增强效果。另外,通过包合实现了TPU 中氨基和 β-CD 中羟基的协同作用, 进而提高了 POM的热稳定性。  48105

毕业论文关键词:聚甲醛; 包合物; 刚韧平衡

Abstract As  one of the five engineering materials, Polyoxymethylene (POM)  shows excellent strength and rigidity, but the toughness and thermal stability are poor. To blend POM with rubber is most efficient way to improve the toughness of POM. Thermoplastic polyurethane elastomer (TPU) is one of the best toughening modifier. Excellent toughness is obtained after adding TPU to POM matrix at the expense of strength, modulus and hardness. Recent years, the study of  inclusion complexes  (ICs) modifying  polymer has received extensive attention. Due to their special "subject-object" structure, ICs  can effectively improve the performance of the polymer. We innovatively prepared the ICs including TPU and β-CD.  In this paper, we  found that the blend POM/IC-TPU(1-1) exhibited  excellent properties. Not only achieved  the desired effect of toughness-stiffness balance, but also enhanced  the thermal stability of POM. Further found that the special structure of "soft shell-hard core" contribute to the excellent properties: "soft shell" improved the toughness of POM and the "hard core" compensated for the loss of strength and modulus because of elastomeric toughening. In addition, the cooperation of amino and hydroxy groups was achieved by inclusion complexes  and such combination siginificantly enhanced the thermostability of POM.  Keyword: polyoxymethylene;  inclusion complex;  stiffness-toughness balance

目录

摘要.I

Abstract..II

目录.III

第1章引言.1

1.1聚甲醛的概述.1

1.1.1聚甲醛的发展1

1.1.2聚甲醛的结构1

1.2聚甲醛的改性.2

1.2.1聚甲醛的稳定化研究2

1.2.1.1抗氧剂..3

1.2.1.2甲醛吸收剂3

1.2.1.3甲酸吸收剂3

1.2.2聚甲醛的增韧改性研究..3

1.2.2.1弹性体增韧改性.3

1.2.2.2刚性粒子增韧改性4

1.2.2.3合金化改性4

1.2.3聚甲醛的增强改性研究..4

1.2.3.1纤维增强改性..4

1.2.3.2无机粉末增强改性5

1.3包合物的研究.5

1.4本文的研究思路以及主要的研究内容6

第2章IC-TPUs对聚甲醛的改性研究..8

2.1主要原料与试剂8

2.2主要仪器与设备8

2.3制备过程9

2.3.1包合物POM/IC-TPU(1-1)的制备.9

2.3.2共混物POM/IC-TPUs的制备.9

2.3.3测试样品的制备..9

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