Poly(methylmethacrylate) (PMMA) shows high strength and transparency but is a flammable material. In this study, the surface of aluminum hydroxide was modified with methacrylate containing phosphoric acid moieties before dispersion in MMA, and organic-inorganic nano-hybrid materials were obtained by bulk polymerization in the presence of the surface-modified aluminum hydroxide. The resulting hybrid materials retained the high transparency of PMMA, with transparency values similar to that of pure PMMA. Moreover, the flame resistance of the hybrid materials was improved in comparison with that of pure PMMA, with depression of the horizontal burning rate becoming a maximum at an inorganic content of 3 wt%. These results suggest that the use of aluminum hydroxide surface-modified with phosphoric acid groups is an efficient method for obtaining good performance fire-resistant polymer materials. 相似文献
Summary: Organic‐inorganic hybrid materials consisting of nanosized silica particles with surface grafted PS or PS‐b‐PMMA were synthesized using ATRP. These hybrid materials were used in the fabrication of highly‐ordered isoporous membranes. Optical characterization revealed that the membranes consisted of hexagonally ordered pores of uniform size. The combination of an open pore structure and high surface area makes isoporous membranes into materials of high interest in fields as biotechnology and photonics.
Image from optical microscope of hybrid nanoparticle membrane of SiO2‐g‐PS with hexagonally‐ordered pores. 相似文献
In this article, the poly(methyl methacrylate)/montmorillonite (PMMA/MMT) organic-inorganic hybrid materials were prepared by conventional free radical polymerization and reversible addition-fragmentation chain transfer (RAFT) polymerization, respectively. The kinetics comparison of these two polymerizations was studied. The PMMA/MMT hybrid materials were characterized by gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). According to these results, we knew that the polymerization behavior of MMA showed controlled/living radical polymerization (CLRP) characteristics under the control of RAFT agent. The incorporation of RAFT agent and MMT nanoparticles improved the thermal properties of polymers, and the thermal stability of polymers increased with increasing content of MMT nanoparticles. The structures and morphologies of PMMA/MMT hybrid materials were characterized by FT-IR, XRD and TEM. These results showed that the MMA monomer can be initiated and propagated in the clay layers of MMT via the control of RAFT agent, and then the exfoliated structure was obtained for the hybrid materials. 相似文献
A plasmonic Ag/AgBr nanohybrid has been synthesized by in situ thermal reduction of AgBr nanoparticles in polyols. This directly converted Ag/AgBr shows significant absorption over the full visible spectrum. The enhanced light absorption in the spectral region of 450 nm to 800 nm was due to the plasmonic nanosized Ag grown on the surface of AgBr nanoparticles with mixed morphologies and increased sizes. Under visible light irradiation, the plasmonic Ag/AgBr exhibits high activity and stability for the photodegradation of organic pollutants, e.g. methylene blue. The contribution of the SPR and its synergistic effect with the photosensitive AgBr in the photocatalytic activity were verified. Based on the plasmon-mediated charge injection and the band structure of the metal-semiconductor heterojunction, a mechanism of the plasmon synergistically enhanced photocatalytic process was proposed. 相似文献
Hybrid materials doped with novel europium complexes were synthesized using PMMA‐co‐Sn12Clusters (copolymers from oxohydroxo‐organotin dimethacrylate and methylmethacrylate) as the matrix material. Two types of hybrid materials were obtained: the physically doped product, PMMA‐co‐Sn12Cluster/Eu(TTA)3phen, and the grafted product, PMMA‐co‐Sn12Cluster‐co‐[EuAA(TTA)2phen] (TTA=2‐thenoyltrifluoroacetone, phen=phenanthroline and AA=acrylic acid). The hybrid materials exhibited characteristic luminescence of the Eu3+ ions, and also showed relative especial optical properties compared with samples just using PMMA as the matrix material. The PMMA‐co‐Sn12Cluster matrix exhibited a high physical doping quantity of [Eu(TTA)3phen], which can be attributed to the special structure of this kind of hybrid material. GPC (gel‐permeation chromatography), TGA (thermogravimetric analysis), SEM, 1H NMR, ICP (inductively coupled plasma), 119Sn NMR, FTIR, and diffuse reflectance techniques were employed to characterize the structures and properties of these hybrid materials. 相似文献