中国塑料 ›› 2021, Vol. 35 ›› Issue (11): 1-6.DOI: 10.19491/j.issn.1001-9278.2021.11.001

• 材料与性能 •    下一篇

超支化聚酰胺强化热塑性聚氨酯结晶及发泡性能的研究

董炳廷, 臧萌, 尹凯, 信春玲(), 何亚东   

  1. 北京化工大学机电工程学院,北京 100029
  • 收稿日期:2021-03-12 出版日期:2021-11-26 发布日期:2021-11-23

Study on Crystallization and Foaming Properties of Hyperbranched Polyamide⁃reinforced Thermoplastic Polyurethane

DONG Bingting, ZANG Meng, YIN Kai, XIN Chunling(), HE Yadong   

  1. College of Mechanical and Electrical Engineering,Beijing University of Chemical Technology,Beijing 100029,China
  • Received:2021-03-12 Online:2021-11-26 Published:2021-11-23
  • Contact: XIN Chunling E-mail:xinxl@mail.buct.edu.cn

摘要:

在热塑性聚氨酯(TPU)中引入超支化聚酰胺HyPer,利用傅里叶红外光谱研究了HyPer对TPU分子间氢键的影响;同时采用旋转流变仪及差示扫描量热仪研究了HyPer对TPU的结晶及流变性能的影响规律。结果表明,HyPer可以与TPU中的氨基甲酸酯形成分子间氢键,显著提高了TPU中羰基峰的氢键化程度; 另外,HyPer的加入对TPU有显著的增塑作用,特性黏度降低,分子间活动能力增加,提高了TPU的结晶速率和结晶度;添加0.25 %(质量分数,下同)的HyPer降低了TPU的熔体黏弹性,有利于泡孔生长,发泡倍率提高30 %,而HyPer含量提高增强了 TPU的结晶度,结晶度的提高一方面可以促进泡孔成核,另一方面可以抑制泡孔生长,有利于泡孔密度的提高,泡孔尺寸的减小。

关键词: 热塑性聚氨酯, 超支化聚酰胺, 分子间氢键, 结晶, 发泡

Abstract:

Hyperbranched polyamide (HyPer) was introduced into thermoplastic polyurethane (TPU), and the effect of HyPer on the intermolecular hydrogen bond of TPU was investigated by Fourier?transform infrared spectroscopy. The effect of HyPer on the crystallization and rheological properties of TPU were evaluated using rotational rheometer and differential scanning calorimeter. The results indicated that HyPer could form intermolecular hydrogen bonds with carbamates in TPU, resulting in a significantly improvement in the degree of hydrogen bonding of carbonyl peak in TPU. In addition, the addition of HyPer generated a significant plasticizing effect on TPU, reducing its intrinsic viscosity, increa?sing its intermolecular mobility, and improving its crystallization rate and crystallinity. The batch?foaming experimental results demonstrated that the addition of 0.25 wt % HyPer reduced the melt viscoelasticity of TPU. This is beneficial to the cell growth and leads to an increase in foaming ratio by 30 %. The increase of hyper content enhanced the crystallinity of TPU. The existence of microcrystalline not only promoted the cell nucleation but also inhibited the cell growth. This facilitates the increase of cell density and the decrease of cell size.

Key words: thermoplastic polyurethane, hyperbranched polyamide, intermolecular hydrogen bond, crystallization, foaming

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