With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by prep...With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by preparation of polymer blends gives rise to new materials with tailored properties. More complex, three-component systems, obtained by the addition of polymeric modifier to polymer filled composites may be of interest. Use of Fly ash cenospheres is very attractive because it is inexpensive and its use can reduce the environmental pollution to a significant extent. In the present study, Poly (Methyl Methacrylate) (PMMA)-Fly ash cenospheres composites were prepared using extrusion followed by Injection molding. The effect of matrix modification with Methyl methacrylate– acrylonitrile -butadiene–styrene (MABS) on the performance of PMMA- Fly ash cenospheres compositions was also, studied. It was found that with the addition of Fly ash cenospheres particulate as filler in PMMA showed marginal reduction in Tensile Strength, % Elongation and Impact strength and improvement in Flexural Strength, Heat Deflection Temperature and Vicat Softening Point. Compared with PMMA-cenospheres composites, the notched Impact Strength of the PMMA/MABS/cenospheres composites showed marginal enhancement in values at higher loading of cenospheres. The optimum performances in mechanical and thermal properties were obtained when the ratio of MABS to cenospheres was 1:2.展开更多
A new kind of polymethyl methacrylate （PMMA）-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples we...A new kind of polymethyl methacrylate （PMMA）-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples were characterized by scanning electron microscopy （SEM）, UV-Vis spectroscopy, differential thermal analysis （DTA） and the photo-induced weight loss, The results show that the photostability of the PMMA-TiO2 nanocomposite is higher than that of the pure PMMA under UV-light irradiation, The weight loss of the pure PMMA reaches 30 % after 300 h UVirradiation, while the composite only 0.3% under the identical experimental condition. The glass transition temperature （TR） of pure PMMA is only 80℃, while the Tg of the composite reaches 258℃. Compared with pure PMMA, the thermal stability of the composite is greatly enhanced.展开更多
Poly(methyl methacrylate)-titania hybrid glasses were synthesized by sol-gel processes using acrylic acid or allyl acetylacetone as coupling agent. Titanium butoxide modified with acrylic acid (or titanium isopropoxid...Poly(methyl methacrylate)-titania hybrid glasses were synthesized by sol-gel processes using acrylic acid or allyl acetylacetone as coupling agent. Titanium butoxide modified with acrylic acid (or titanium isopropoxide modified with allyl acetylacetone) was hydrolyzed to produce a titania network, and then poly(methyl methacrylate) (PMMA)chains formed in situ through a radical polymerization were chendcally bonded to the fortheng titania network to synthesize a hybrid glass. Transparent hybrid glasses with different contents of titania were achieved. With the increase of the titania content, the color of the products changed from yellow to red. The synthesis process was investigated stepwise by using FTIR spectroscopies, and the experimental results demonstrated that acrylic or acetylacetonate groups bound to titanium remain in the final hybrid glasses.The thermal stability of the hybrid materials were considerably improved relative to pure PMMA. The hybrid glasses using allyl acetylacetone as coupling agent exhibited ther mochromatic effect which both pure PMMA and titan ia do not manifest.展开更多
文摘With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by preparation of polymer blends gives rise to new materials with tailored properties. More complex, three-component systems, obtained by the addition of polymeric modifier to polymer filled composites may be of interest. Use of Fly ash cenospheres is very attractive because it is inexpensive and its use can reduce the environmental pollution to a significant extent. In the present study, Poly (Methyl Methacrylate) (PMMA)-Fly ash cenospheres composites were prepared using extrusion followed by Injection molding. The effect of matrix modification with Methyl methacrylate– acrylonitrile -butadiene–styrene (MABS) on the performance of PMMA- Fly ash cenospheres compositions was also, studied. It was found that with the addition of Fly ash cenospheres particulate as filler in PMMA showed marginal reduction in Tensile Strength, % Elongation and Impact strength and improvement in Flexural Strength, Heat Deflection Temperature and Vicat Softening Point. Compared with PMMA-cenospheres composites, the notched Impact Strength of the PMMA/MABS/cenospheres composites showed marginal enhancement in values at higher loading of cenospheres. The optimum performances in mechanical and thermal properties were obtained when the ratio of MABS to cenospheres was 1:2.
文摘A new kind of polymethyl methacrylate （PMMA）-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples were characterized by scanning electron microscopy （SEM）, UV-Vis spectroscopy, differential thermal analysis （DTA） and the photo-induced weight loss, The results show that the photostability of the PMMA-TiO2 nanocomposite is higher than that of the pure PMMA under UV-light irradiation, The weight loss of the pure PMMA reaches 30 % after 300 h UVirradiation, while the composite only 0.3% under the identical experimental condition. The glass transition temperature （TR） of pure PMMA is only 80℃, while the Tg of the composite reaches 258℃. Compared with pure PMMA, the thermal stability of the composite is greatly enhanced.
文摘Poly(methyl methacrylate)-titania hybrid glasses were synthesized by sol-gel processes using acrylic acid or allyl acetylacetone as coupling agent. Titanium butoxide modified with acrylic acid (or titanium isopropoxide modified with allyl acetylacetone) was hydrolyzed to produce a titania network, and then poly(methyl methacrylate) (PMMA)chains formed in situ through a radical polymerization were chendcally bonded to the fortheng titania network to synthesize a hybrid glass. Transparent hybrid glasses with different contents of titania were achieved. With the increase of the titania content, the color of the products changed from yellow to red. The synthesis process was investigated stepwise by using FTIR spectroscopies, and the experimental results demonstrated that acrylic or acetylacetonate groups bound to titanium remain in the final hybrid glasses.The thermal stability of the hybrid materials were considerably improved relative to pure PMMA. The hybrid glasses using allyl acetylacetone as coupling agent exhibited ther mochromatic effect which both pure PMMA and titan ia do not manifest.
