水性聚氨酯的改性及其复合材料的制备与研究

发布时间：2018-04-27 07:03

本文选题：水性聚氨酯 + γ-氨丙基三乙氧基硅烷　；参考：《武汉理工大学》2015年硕士论文

【摘要】：水性聚氨酯(WPU)的力学性能和耐水性具有很大的可调性,调节软段的不同种类,WPU可获得不同的优异性能。聚醚作为软段可制备出耐水解性相对较好的WPU胶膜,聚酯作为软段可改善其涂膜的外观平滑和光亮等性能,本论文首先采用预聚体法以聚醚/聚酯为混合软段成功合成出了混合型WPU乳液;由于其混合型WPU结构设计属于线型分子链段,导致其本身结构构造存在缺陷,为了进一步改善其成膜后的成品的力学性能、耐水性和热稳定性等,以γ-氨丙基三乙氧基硅烷(APTES)为硅烷偶联剂和三羟甲基氨基甲烷(TOAM)为交联剂来成功制备出硅烷改性水性聚氨酯(PUSi)乳液;最后以聚己二酸-1,4-丁二醇酯二醇(PBA)插层有机蒙脱土(OMMT),再将其与混合型WPU复合,合成出了HPU/OMMT纳米复合材料,其材料表现出较佳的力学性能和热稳定性。本论文的主要研究内容如下:(1)研究了软段链中PBA与聚四氢呋喃醚二醇(PTMG)的质量比对乳液的平均粒径、黏度、Zeta电位、接触角、吸水率、力学性能和热稳定性等影响;再以PTMG/PBA为混合软段,研究了R值、DMPA含量和扩链剂含量等因素对乳液和胶膜性能的影响。(2)以APTES作为硅烷偶联剂和TOAM作为交联剂,成功合成出了硅烷改性交联型WPU乳液(PUSi);研究了APTES用量对PUSi乳液的粒径和形貌,PUSi胶膜的耐水性、力学性能和热性能等的影响。研究发现,APTES加入到WPU预聚体中后,降低了N-H与C=O间的氢键化程度,增加了软硬段间的兼容性,导致25.6°和43.3°处的软硬段结晶峰消失,PUSi胶膜的玻璃化转变温度(Tg)升高。(3)采用十六烷基三甲基溴化铵(CTAB)对钠基蒙脱土(Na-MMT)进行有机改性,形成了有机蒙脱土(OMMT),以PBA插层OMMT,形成了PBA/OMMT;再以PBA/OMMT作为基料,成功制备出的HPU/OMMT纳米复合材料。FTIR分析表明,HPU/OMMT中出现了534cm-1处Al-O伸缩振动峰和467cm-1处Si-O伸缩振动峰,表明已成功合成出HPU/OMMT乳液;WXRD分析表明,当OMMT用量为1%时,PU链段已插入到OMMT中,OMMT呈剥离态;当OMMT用量大于5%时,PBA/OMMT会在HPU乳液中发生沉积。DSC曲线表明,PBA/OMMT与HPU形成悬挂链,提高了软硬段兼容性,导致软硬段熔融温度下降;OMMT的加入会导致分子链的运动受阻,主链的柔顺性变差,复合材料的Tg升高。
[Abstract]:The mechanical properties and water resistance of waterborne polyurethane (WPU) have great tunability, and different kinds of soft segments can be adjusted. WPU can obtain different excellent properties. Polyether can be used as soft segment to prepare WPU film with relatively good hydrolysis resistance. As a soft segment, polyesters can improve the exterior smooth and bright properties of the film. The prepolymerization of this paper is first used in this paper. The hybrid WPU emulsion was successfully synthesized with polyether / polyester as a mixed soft segment. Because its hybrid WPU structure was designed to be a linear molecular chain, its structure and structure existed defects. In order to further improve the mechanical properties, water resistance and thermal stability of the finished product, gamma propyl triethoxyl silane (APTES) was used to improve its mechanical properties. Silane coupling agent and three hydroxymethyl amino methane (TOAM) were used as crosslinker to prepare silane modified waterborne polyurethane (PUSi) emulsion. Finally, polydiol -1,4- butanediol diol (PBA) intercalated organic montmorillonite (OMMT) was used to compounded it with mixed WPU and formed a HPU/OMMT nanocomposite. The material showed better force. The main contents of this thesis are as follows: (1) the effects of mass ratio of PBA and polytetrahydrofuran ether glycol (PTMG) in soft segment chain on the average particle size, viscosity, Zeta potential, contact angle, water absorption, mechanical properties and thermal stability of the emulsion were studied. The R value, DMPA content and chain expansion were studied with PTMG/PBA as a mixed soft segment. The effect of agent content on the properties of emulsion and film. (2) APTES as silane coupling agent and TOAM as crosslinker, a silane modified intercourse WPU emulsion (PUSi) was successfully synthesized. The effect of APTES dosage on the particle size and morphology of PUSi emulsion, the water resistance, mechanical properties and thermal properties of the PUSi adhesive film were studied. The study found that APTES was added to the emulsion. After the WPU prepolymer, the degree of hydrogen bonding between N-H and C=O was reduced, the compatibility between the soft and hard segments was increased, the crystallization peak of the soft and hard segments at 25.6 and 43.3 degrees disappeared and the glass transition temperature (Tg) of the PUSi film increased. (3) the organic modification was made with sixteen alkyl three methyl ammonium bromide (CTAB) to the sodium base montmorillonite (Na-MMT) and formed organic matter. Montmorillonite (OMMT), PBA/OMMT was formed with PBA intercalated OMMT, and then PBA/OMMT was used as the base material. The.FTIR analysis of the HPU/OMMT nanocomposite prepared successfully showed that the Al-O expansion vibration peak of 534cm-1 and the Si-O expansion vibration peak at 534cm-1 were found in HPU/OMMT, which showed that the emulsion had been successfully synthesized. The PU segment has been inserted into OMMT and OMMT is stripped. When the OMMT dosage is more than 5%, PBA/OMMT will deposit.DSC curves in HPU emulsion indicating that PBA/OMMT and HPU form a suspension chain, which improves the compatibility of the soft and hard segments and leads to the melting temperature of the soft and hard segments, and the addition of OMMT will lead to the resistance of the molecular chain, the flexibility of the main chain, and the composite material. The Tg of the material increases.

【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ317;TB33

【参考文献】