当前位置: X-MOL 学术Green Chem. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Facile synthesis of starch-based nanoparticle stabilized Pickering emulsion: its pH-responsive behavior and application for recyclable catalysis
Green Chemistry ( IF 9.3 ) Pub Date : 2018-02-14 00:00:00 , DOI: 10.1039/c8gc00143j
Liang Qi 1, 2, 3, 4 , Zhigang Luo 1, 2, 3, 4, 5 , Xuanxuan Lu 6, 7, 8, 9, 10
Affiliation  

In this work, a pH-responsive [2-(dimethylamine)ethyl methacrylate] (DMAEMA) grafted maize starch composite was synthesized via free radical polymerization in the presence of the crosslinker N,N′-methylenebisacrylamide (BIS). Combined with the gelatinization–ethanol precipitation process, this starch-based composite in an optimized component ratio showed a nanometer size and regular spherical shape, along with a high freedom of the molecular chain, which was not only a breakthrough in terms of structure, but also brought about an outstanding performance in pH-responsiveness. Its superiority was proved by the formation of a Pickering emulsion that underwent pH-induced reversible emulsification/demulsification for at least 8 cycles without obvious performance decay or even morphology changes. Dynamic light scattering, zeta potential measurement and interfacial tension measurement, as well as contact angle measurement, confirmed synergistically that the reversible emulsification/demulsification cycle was the result of the tunable wettability and size of these novel starch-based nanoparticles under pH variation. More importantly, benefitting from DMAEMA as the stabilizer and growth point for Au nanoparticles and the large interfacial area of the emulsion droplets together with the pH-responsive reversible emulsification/demulsification cycle, the generated Pickering emulsion could be readily applied as catalytic microreactors for the hydrogenation of p-nitroanisole at the oil–water interface. This catalysis exhibited both high catalytic activity and good recyclability. The excellent performance makes us believe that this system is promising for meeting the requirements of green and sustainable chemistry.

中文翻译:

淀粉基纳米颗粒稳定的Pickering乳液的简便合成:pH响应行为及其在可循环催化中的应用

在这项工作中,在交联剂NN的存在下,通过自由基聚合反应合成了pH响应型[甲基丙烯酸2-(二甲胺)乙酯](DMAEMA)接枝的玉米淀粉复合材料。′-亚甲基双丙烯酰胺(BIS)。结合糊化-乙醇沉淀过程,该淀粉基复合材料以最佳的组分比率显示出纳米级尺寸和规则的球形,并具有较高的分子链自由度,这不仅是结构上的突破,而且还带来了出色的pH响应性能。它的优越性通过形成Pickering乳液而得到证明,该乳液经过pH诱导的可逆乳化/反乳化至少8个循环而没有明显的性能下降甚至形态变化。动态光散射,ζ电势测量和界面张力测量以及接触角测量,协同证实,可逆的乳化/破乳循环是这些新型淀粉基纳米粒子在pH值变化下可调节的润湿性和尺寸的结果。更重要的是,得益于DMAEMA作为Au纳米颗粒的稳定剂和生长点,以及乳液液滴的大界面面积以及pH响应可逆的乳化/破乳循环,所产生的Pickering乳液可以很容易地用作氢化的催化微反应器。的在油-水界面处的硝基苯甲醚。这种催化表现出高的催化活性和良好的可回收性。出色的性能使我们相信该系统有望满足绿色和可持续化学的要求。
更新日期:2018-04-03
down
wechat
bug