空心纳米网络结构聚苯乙烯及其炭材料的制备与结构调控

研究了纳米网络结构聚苯乙烯及其炭材料的结构设计、可控合成及其构效关系.以二氧化硅为载体,通过表面引发原子转移自由基聚合-傅克超交联联合法成功在分子水平上设计制备出具有空心微孔聚苯乙烯纳米球网络单元的三维纳米网络结构聚苯乙烯(HNNS-PS),并通过控制PS分子量对三维纳米网络结构进行调控.通过凝胶渗透色谱(GPC)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、热重分析(TGA)、N2吸附等手段考察HNNS-PS的纳米结构和形貌,利用IGA研究HNNS-PS的有机蒸汽吸附性能,并通过升温速率控制实现三维纳米网络结构在炭化过程中的可继承性.结果表明,通过调控PS分子量HNNS-PS网络单元粒径为263~332 nm,PS分子量越大,BET比表面积(BrunauerEmmett-Teller specific surface area,SBET)越大,最高可达450 m2 g-1,甲苯蒸汽吸附量最高可达534 mg g-1.此外,当炭化升温速率较低(1~2 K min-1)时,制得的空心纳米球炭网络保留了典型的三维纳米网络结构形貌,SBET最高可达696 m2 g-1.

Fabrication of Silver Yolk@Porous Janus Polymer Shell Nanospheres for Synergistic Catalysis

Yolk-shell nanostructures have recently attracted tremendous research interests in various areas because of their unique structural merits.Currently,there is an urgent need for developing porous shells with multifunctional features to enhance their performance in various applications.Herein,advanced yolk-shell nanospheres have been facilely prepared by encapsulating silver nanoparticles with porous Janus polymer shells that consist of a hypercrosslinked polystyrene(xPS)outer layer and a tethered poly(acrylic acid)(PAA)brush lining.The xPS outer layer possesses well-developed porosity as mass diffusion pathways.More importantly,the tethered PAA brushes with customized carboxyl groups exhibit great affinity toward specific species(e.g.,cationic dyes),leading to their enrichment from the bulk solution into the interior cavity.The unusual combination of highly porous outer layers with customizable inbuilt polymer linings in the porous Janus shells endows them with great promise for synergistically catalytic degradation of cationic dyes.