Preparation of poly(methyl methacrylate)‐Silica nanoparticles via differential microemulsion polymerization and physical properties of NR/PMMA‐SiO₂ hybrid membranes

Abstract

Poly(methy methacrylate) (PMMA)-SiO 2 nanoparticles were prepared via differential microemulsion polymerization. The effects of silica loading, surfactant concentration, and initiator concentration on monomer conversion, particle size, particle size distribution, grafting efficiency, and silica encapsulation efficiency were investigated. A high monomer conversion of 99.9% and PMMA-SiO 2 nanoparticles with a size range of 30 to 50 nm were obtained at a low surfactant concentration of 5.34 wt% based on monomer. PMMA-SiO 2 nanoparticles showed spherical particles with a core-shell morphology by TEM micrographs. A nanocomposite membrane from natural rubber (NR) and PMMA-SiO 2 emulsion was studied for mechanical and thermal properties and pervaporation of water-ethanol mixtures. PMMA-SiO 2 nanoparticles which were uniformly dispersed in NR matrix, significantly enhanced mechanical properties and showed high water selectivity in permeate flux. Thus, the NR/PMMA-SiO 2 hybrid membranes have great potential for pervaporation process in membrane applications. POLYM. ENG. SCI.,

Synthesis and characterization of highly durable and reusable superabsorbent core–shell particles

“…a) obtained from co‐condensation of TEOS and VTES showed two characteristic peaks at 1630 and 1,409 cm −1 , which were the signals of CC in plane deformation and C─H out of plain bending, respectively. These peaks confirmed the existing of vinyl groups on the surface of the particles . The spectra of all compositions of SiO 2 ‐PAM hybrid nanoparticles presented peaks at 3400, 2922, 1,670, and 1,454 cm −1 , attributed to N─H stretching overlapping with ─OH stretching, C─H stretching, CO stretching for amide I, and C─H bending of amide, respectively .…”

Grafting polyisoprene onto surfaces of nanosilica via RAFT polymerization and modification of natural rubber

“…With the development of controlled radical polymerization (CRP), there have been many reports on grafting a polymer onto the surface of nano‐SiO 2 by way of CRP. Polystyrene, poly(methyl methacrylate), polybutyrate, poly(methylacrylamide), and so on have been grafted onto the surface of nano‐SiO 2 via atomic transfer radical polymerization (ATRP) or RAFT polymerization .…”

Reinforcing Poly(methyl methacrylate) with Bacterial Cellulose Nanofibers Chemically Modified with Methacryolyl Groups

“…A popular way of enhancing the mechanical properties of PMMA involves producing composite materials with microfillers, such as glass [ 5 ], polyethylene [ 6 ], aramid fiber [ 7 ], carbon fiber [ 8 ], silica or glass particles [ 8 , 9 ], and stainless steel mesh [ 10 ]. According to previous studies [ 5 , 6 , 7 , 8 , 9 , 10 ], these fillers slightly increase the flexural and impact strengths of PMMA; however, their use is limited because the addition of the filler generally reduces the transparency of the polymer [ 9 ], which is one of the most important features of PMMA resin. At the same time, the formation of a PMMA/filler interface often reduces the tension strain limit owing to the effects of structural heterogeneity and interfacial adhesion [ 11 , 12 , 13 ].…”

“…At the same time, the formation of a PMMA/filler interface often reduces the tension strain limit owing to the effects of structural heterogeneity and interfacial adhesion [ 11 , 12 , 13 ]. Therefore, various types of micro- and nanofiber, including carbon, aramid, and ultra high-molecular-weight polystyrene, have been investigated as reinforcing fillers that enhance the mechanical properties of PMMA [ 7 , 8 , 14 ]. Unfortunately, these fillers absorb stress and energy inadequately, which leads to structural deficiencies, a lack of rigidity, and inhomogeneous filler setting that, in turn, result in a fragile and fractured composite [ 15 ].…”