The synthesis, characterisation and application of novel high-density poly(vinylsulfonic acid)-grafted solid acid catalysts are described. A graft, radical polymerization procedure was employed, allowing the immobilisation of the acid form of vinylsulfonic acid monomer onto various carrier materials, such as polystyrene, silica or polysaccharide-based gels. The highest acid-exchange capacity (as determined by acid–base titration methods) achieved with these new materials was 5.2 mmol H+ g−1. The properties of these PVS-grafted materials as solid state acid catalysts have been examined from several perspectives, including their fundamental properties as materials with extremely high acid dissociation characteristics, their structural features as revealed from IR and solid-state NMR measurements, their thermal stability properties, and their surface morphologies, humidity dependencies and functionality. Compared to many other types of acid catalysts, these high-density poly(vinylsulfonic acid)-grafted materials demonstrated superior catalytic performance in esterification, Friedel–Crafts acylation, and condensation reactions. Moreover, these novel materials show high stability, significant anticorrosion capability and can be easily recycled.
本文描述了新型高密度聚
乙烯磺酸(PVS)接枝固体酸催化剂的合成、表征和应用。采用接枝自由基聚合方法,将
乙烯磺酸单体的酸态固定在各种载体材料上,如聚
苯乙烯、
硅胶或基于
多糖的凝胶等。通过酸碱滴定法测定,这些新材料的最大酸交换容量达到5.2毫摩尔H+/克。从多个角度考察了这些PVS接枝材料作为固体酸催化剂的性能,包括它们作为具有极高酸性解离特性的材料的基态性质、通过红外光谱和固体核磁共振测量揭示的结构特征、热稳定性、表面形貌、湿度和功能性等方面的影响。与许多其他类型的酸催化剂相比,这些高密度聚
乙烯磺酸接枝材料在酯化、Friedel-Crafts酰基化、缩合反应等方面表现出更优异的催化性能。此外,这些新材料表现出高度的稳定性、显著的防腐能力和易于回收的特点。