Papers by Keyword: Expandable Polystyrene

Abstract: There are exposed the results of resistance testing on effects of fire in interfloor construction and wall panel made according to “plastbau” system technology out of expandable polystyrene, when they are protected by mortar extension as an insulator. The applied testing method is prescribed by standard form EN 13501-2. Based on testing results, there is affirmed that interfloor construction fulfills resistance criteria on effects of fire of 180 min, and wall panel fulfills resistance criteria on effects of fire of 60 min, when it is protected by mortar extension as an insulator..

Abstract: With the gradual increase of the global environmental awareness and environmentally friendly voice rising, the deal with the problem of plastic waste has become the focus of public opinion around the world has also become a hot topic of scientific research. This paper can be made of polystyrene as main raw material, adding starch and antibacterial agents containing silver nanoscale titanium dioxide, and by the synthesis of biodegradable packaging materials performance. The results showed that: 0.25mm sheet of polystyrene made of the thickness of the main raw material by injection molding process, and factors affecting the performance of the sheet, the better the performance of the film material process parameters. According to the definition of the GB/T1040-92 national standards of the People's Republic of China "plastic tensile properties of test methods and GB/T20197-2006 degradable plastics, classification, marking, and degradation of the performance requirements" and GB4789.3-94 "State Microbiological examination of coli form bacteria in the standard of food hygiene as determined by experimental methods for testing. The orthogonal experiment results show that the expandable polystyrene Dosage: 80%; starch dosage: 2%; toluene, acetone and put ratio: 3:2 .The mechanics of materials, degradation, and antimicrobial properties.

Abstract: The article by using the coating apparatus of fluidized bed, the surface coating method of the spherical particles of pre-expanded polystyrene (EPS), processing of EPS surface modified; different volatile solvents, as well as an acrylic resin, epoxy, modified polyurethane coating material selection, the EPS particle surface coating processing experiments. The test results show that after the modified material after foaming and mold filling repression through modified EPS material has a lot of improvement in its inter-particle adhesion, impact resistance and strength, the process can be EPS material of high value-added processing to provide a new way.

Abstract: The authors investigate the component fabrication of a flapping ornithopter with 21.6 cm wing span by using precision injection molding. For making a bio-mimicking flapper like birds, two fold of plastic injection moldings have been done. Firstly the flapping mechanism of a 4-bar linkage gear transmission module has been studied, and the according plastic components for the gear transmission module were designed as light as possible. Thereafter the injection flow analysis in the multi-mold cavity and the fabrication parameters of the molding process has been implemented. The finished polyoxymethylene (POM) components for the transmission module of 1.2 gram in mass finally verify the design and process of the precision injection molding. After the ornithopter Golden Snitch was assembled and tested with the fore-mentioned plastic 4-bar linkage, a maximum flight record of 480 sec was created in 2010. The second framework of injection molding is to design a bird-like expandable polystyrene (EPS) fuselage with 19.5 cm in length as the mechanical protection. After this ornithopter Golden Snitch-Pro was assembled, it has a successful flight of 230 sec and 100 times of landing capability. In summary, the fabrication of a polymeric bird-like flapper is proved, and the precision injection molding technique shows its feasibility in realization of ornithopters.

Abstract: In the lost foam casting (LFC) of aluminum alloys, the expandable polystyrene (EPS) foam characteristics (foam composition, polymer processing and bead fusion) influence the formation of deleterious fold defects in the final casting. In this research, four types of EPS beads were investigated: (1) the regular EPS beads, (2) 2wt% hexabromocyclododecane and 2wt% dicumyl peroxide added to the EPS beads during the polymerization process, (3) 2wt% silicaalumina blended to EPS beads after the pre-expansion process of the beads and (4) 2wt% hexabromocyclododecane blended to EPS beads after the pre-expansion process of the beads. The density of the regular and modified EPS beads was kept constant at 25.63 kg/m3. Aluminum alloy A356 was poured at 1023 K into the window pattern. The window patterns with regular EPS beads did not fill completely and had identifiable carbon/oxide defects on the surface. The window patterns with the additives were completely filled with a few surface defects. From thermogravimetric analysis (TGA), it was found that the EPS beads with silica-alumina had a reduced onset temperature of degradation of EPS (from 634 K to 618 K) and a reduced activation energy (from 188 kJ/mol to 147 kJ/mol) relative to the regular beads. In the organic brominatedmodified EPS (both through blending and polymerization), it was found that the value of the preexponential (rate equation) was significantly increased. Through light optical microscopy (LOM) and scanning electron microscopy (SEM), it was found that the polymerization process additives increased the degree of bead fusion whereas the post pre-expansion additives decreased the degree of bead fusion. Finally, the EPS beads treated during the polymerization process produced castings with the least overall surface, subsurface and internal defects.