高耐热聚酰胺62/聚氧乙烯二胺共聚物的制备及性能

为了适当降低高耐热聚酰胺62(PA62)的熔点以改善其熔融加工性能,采用胺酯缩合聚合法将聚氧乙烯二胺(PEG)作为软段引入制备了高分子量PA62/PEG2共聚物。红外光谱和核磁验证了共聚聚草酰胺的成功制备;差示扫描量热分析表明PEG导入抑制了PA62的结晶,有效降低了PA62的熔点和结晶度;热重分析显示,随着PEG的加入,共聚物的热稳定性有所降低,但整体表现良好。WAXD的测试表明,当PEG单元的摩尔含量25%时,共聚物的结晶度虽然随着PEG含量的增加而降低,但仍含有较高的结晶度。结果表明高熔点PA62/PEG2共聚物可以作为一种潜在的高耐热聚酰胺。

聚氧乙烯聚氧丙烯基醚二胺的合成工艺

聚氧乙烯聚氧丙烯基醚二胺(ED-600)是制备有机硅柔软剂的重要原料。采用固定床连续化反应技术合成聚氧乙烯聚氧丙烯基醚二胺,旨在解决羟基胺化的技术瓶颈。主要研究了反应温度、物料配比、空速对转化率的影响。结果表明,优化反应条件为:反应温度155℃,液氨、醇醚物质的量比5∶1,氢气、醇醚物质的量比8∶1,聚醚质量空速0.15 h^(-1)。利用红外光谱核磁共振波谱技术对产品结构进行了表征。

Feature Designed Growth of 3D Flower-like SiO2 Growing on Polyethyleneimine Modified CaCO3 Microparticles

We report on the ability to create complex 3D flower-like SiO2 in vitro via CaCO3 micropar- icles supported by polyethyleneimine mediated biosilicification under experimentally altered chemical influences. The morphology, structure, composition of the product have been inves- tigated with the X-ray photoelectron spectrum, scanning electron microscope, transmission electron microscope, and energy-dispersive spectroscopy. Tile overall morphologies could be controlled to shift from a characteristic network of flower-like silica sphere to a sheet-like structure by adjusting physical adsorption of different amount of polyethyleneimine onto the surface of the CaCO3 microparticles.