紫外屏蔽纳米粒子制备及其在聚苯硫醚抗紫外中的研究

发布时间：2019-06-20 09:57

【摘要】：PPS是一种线型高分子结晶性聚合物,具有优异的热稳定性、耐化学腐蚀性和尺寸稳定性等,可广泛应用于机械行业、纺织行业和航空航天领域等。但由于PPS耐光稳定性差,在长期光照条件下颜色变深,力学性能变差,发生老化,抗紫外性能较差,极大的制约了 PPS在高端领域的应用发展。纳米二氧化钛(TiO_2)作为一种无机紫外吸收剂,可以很好的吸收散射紫外光,紫外屏蔽效果佳,常被用作高聚物抗紫外改性剂。然而常规纳米TiO_2粒径小、比表面积大且表面活性高,掺杂过程中极易发生团聚,影响改性效果,此外TiO_2自身优异的光催化性能会加速PPS基体降解,因此在改性过程中有必要对TiO_2粒子进行修饰,抑制其光催化性能。本课题首先采用凝胶-溶胶法对TiO_2化学修饰,制备了一系列紫外屏蔽纳米粒子 TiO_2@SiO_2、TiO_2@SiO_2/APTES、TiO_2/PTES。对 TiO_2@SiO_2、TiO_2@SiO_2/APTES、TiO_2/PTES纳米粒子进行一系列系统的表征,通过测试其紫外屏蔽性能、光催化性能,筛选出性能相对优异的纳米粒子。研究表明TiO_2@SiO_2/APTES-0.6纳米粒子可以保持TiO_2的紫外屏蔽性能超过80%,同时能有效地抑制TiO_2的光催化性能。TiO_2/PTES-2纳米粒子相比TiO_2@SiO_2/APTES-0.6纳米粒子能更显著地抑制TiO_2的光催化性能,不过由于PTES接枝量过大,却无法保持TiO优异的紫外屏蔽性能。然后将紫外屏蔽性能优异,同时抑制TiO_2的光催化性能优异的TiO_2@SiO_2/APTES-0.6和TiO_2/PTES-2纳米粒子以不同比例加入PPS中,以热致相成膜工艺制备PPS复合薄膜,探讨纳米粒子的掺杂对PPS抗紫外老化性能的影响。研究表明当Ti02@SiO_2/APTES纳米粒子掺杂量为1.0 wt%时,TiO_2@SiO_2/APTES/PPS复合薄膜紫外辐射192h后的断裂强度保留率和断裂伸长保留率分别为88.61%和85.14%,有效提高PPS抗紫外性能;当TiO_2/PTES-2纳米粒子的添加量为2.0 wt%时,TiO_2/PTES/PPS复合薄膜紫外辐射192h后的断裂强度保留率和断裂伸长保留率分别为93.75%和94.00%,PPS抗紫外性能达到最佳。
[Abstract]:PPS is a kind of linear polymer, which has excellent thermal stability, chemical corrosion resistance and dimensional stability. It can be widely used in machinery industry, textile industry and aerospace industry. However, due to the poor light resistance and stability of PPS, the color becomes darker, the mechanical properties become worse, the aging occurs and the UV resistance is poor under long-term light conditions, which greatly restricts the application and development of PPS in high-end fields. Nano-titanium dioxide (TiO_2), as an inorganic ultraviolet absorbent, can absorb and scatter ultraviolet light very well, and the UV shielding effect is good, so it is often used as polymer anti-ultraviolet modifier. However, the size of conventional nano-TiO_2 particles is small, the specific surface area is large and the surface activity is high, so it is easy to agglomeration in the doping process, which affects the modification effect. In addition, the excellent photocatalytic performance of TiO_2 itself will accelerate the degradation of PPS matrix, so it is necessary to modify TiO_2 particles in the modification process to inhibit its photocatalytic performance. In this paper, a series of UV shielded nanoparticles TiO_2@SiO_2,TiO_2@SiO_2/APTES,TiO_2/PTES. were prepared by chemical modification of TiO_2 by gel-sol method. A series of systematic characterization of TiO_2@SiO_2,TiO_2@SiO_2/APTES,TiO_2/PTES nanoparticles was carried out. By testing their UV shielding performance and photocatalytic performance, the nanoparticles with relatively excellent performance were screened out. The results show that TiO_2@SiO_2/APTES-0.6 nanoparticles can maintain the UV shielding performance of TiO_2 more than 80%, and can effectively inhibit the photocatalytic performance of TiO_2. TIO _ 2/PTES-2 nanoparticles can inhibit the photocatalytic performance of TiO_2 more significantly than TiO_2@SiO_2/APTES-0.6 nanoparticles, but because of the large amount of PTES grafting, it can not maintain the excellent UV shielding performance of TiO. Then TiO_2@SiO_2/APTES-0.6 and TiO_2/PTES-2 nanoparticles, which have excellent UV shielding performance and excellent photocatalytic performance of TiO_2, were added to PPS in different proportion. PPS composite thin films were prepared by thermogenic phase formation process. The effect of doping nanoparticles on the UV aging resistance of PPS was discussed. The results show that when the doping content of Ti02@SiO_2/APTES nanoparticles is 1.0 wt%, the retention rates of fracture strength and fracture extension of TiO_2@SiO_2/APTES/PPS composite films are 88.61% and 85.14% respectively after 192 h UV radiation, which can effectively improve the UV resistance of PPS. When the content of TiO_2/PTES-2 nanoparticles was 2.0 wt%, the retention rates of breaking strength and breaking extension of TiO_2/PTES/PPS composite films were 93.75% and 94.00%, respectively, and the UV resistance of PPS composite films was the best.
【学位授予单位】：天津工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.1;TQ326.56

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