Plastic thermo

Deutsches Institut fur Normung e. V. (DIN) Plastics - Thermo-mechanical analysis (TMA). Berlin Beuth-Veriag, 1999-... 

Polyamides, like other macromolecules, degrade as a result of mechanical stress either in the melt phase, in solution, or in the soHd state (124). Degradation in the fluid state is usually detected via a change in viscosity or molecular weight distribution (125). However, in the soHd state it is possible to observe the free radicals formed as a result of polymer chains breaking under the appHed stress. If the polymer is protected from oxygen, then alkyl radicals can be observed (126). However, if the sample is exposed to air then the radicals react with oxygen in a manner similar to thermo- and photooxidation. These reactions lead to the formation of microcracks, embrittlement, and fracture, which can eventually result in failure of the fiber, film, or plastic article. 

Y.L. Bai, Thermo-Plastic Instability in Simple Shear, J. Mech. Phys. Solids 30, 195-207 (1982). 

The chassis is made from a 1/4 in. sheet of either ABS or TPO vacuum formed into a tub and reinforced with reinforced pultruded glass fiber-TS polyester plastic tubing. The hood and other products are being made from a 20 mm thick sandwich of thermo-formed PPO-alloy skins, glass fabric infused with thermosetting vinyl ester, and a urethane foam core. The bumper and front fascia is thermoformed from a polyolefin elastomer sheet with an UV-resistant cap layer of DuPont s Tediar PVF film. The dash and... 

Ljungberg, N. and Wesslen, B. 2003. Tributyl citrate oligomers as plasticizers for polyjlactic add) Thermo-mechanical film properties and aging. Polymer 44 7679-7688. 

In practice, synthetic polymers are sometimes divided into two classes, thermosetting and thermo-plastic. Those polymers which in their original condition will flow and can be moulded by heat and pressme, but which in their finished or cured gtate cannot be re-softened or moulded are known as thermo setting (examples phenol formaldehyde or urea formaldehyde polymer). Thermoplastic polymers can be resoftened and remoulded by heat (examples ethylene polymers and polymers of acrylic esters). 

Graphite/ Thermo- plastic AS4/PPS Phillips Petroleum Phillips Petroleum Polyphenylene sulfide, semicrystalline thermoplastic... 

The characteristic property of elastomers is their rubber-elastic behavior. Their softening temperature lies below room temperature. In the unvulcanized state, i.e. without crosslinking of the molecular chains, elastomers are plastic and thermo-formable, but in the vulcanized state—within a certain temperature range — they deform elastically. Vulcanization converts natural rubber into the elastic state. A large number of synthetic rubber types and elastomers are known and available on the market. They have a number of specially improved properties over crude rubber, some of them having substantially improved elasticity, heat, low-temperature, weathering and oxidation resistance, wear resistance, resistance to different chemicals, oils etc. 

True synthetic polymers came into use when Bakeland came from Belgium and applied his knowledge of the formation of a moldable plastic from phenol and formaldehyde to give the product named Bakelite. This was about 1914. This product, under heat and pressure, set up to a thermo-setting resin and had useful properties especially as an insulating material for electrical items. 

Cast and extruded sheets, cell-cast sheets, stretched sheets, films down to 50 microns laminated protective surfaces on ABS, PVC or other plastic sheets that are thermo-formed into parts requiring resistance to outdoor weathering for residential siding and transformer housings... 

Pb azide, Pb nitrophenols, Pb triethanol-ammonium perchlorate and PETN or RDX, with a sheath spun from filaments of a thermo plastic material or a ductile metal such as bronze) Ad 159) J.F. Kenney, USP 3293091(1966) CA 67, 7089(1967) [Primary expl mixts contg 46% of complex clathrate inclusion salts (as shown by X-ray diffraction data) of basic lead picrate, such as Pb(C5H2N3O7)2-Pb(OH)2-Pb(N03)2.-Pb(OAc)2, 50% Ba nitrate 4% Tetracene]... 

Particle Particle size (pm) Thermo- Loading plastic matrix (vol.%) Temperature (°C) Yield value (kPa)... 

Schultz. J.VI. Polymer Crystallization The Development of Crystalline in Thermo plastic Polymers. Oxford University Press. Inc., New York. NY. 2001. 

Attempts to give a quantitative analysis of plastisol extrusion were undertaken only in a few published papers. They were based on the analysis of plastisol viscosity as a function of temperature and time. If in the processing of thermosetting plastics their viscosity is assumed as practically independent of time (except of materials sensitive to structural and chemical transformation in temperature and stress fields which are accompanied by thermo-mechanical decomposition and cross-linking of macromolecular chains, the extent of the larter being influenced by the time of exposure to thermal and mechanical loads 18-21)), then at extrusion of plastisols, in view of their gelatination, the additional condition should be satisfield ... 

Figure I. Composite tensile strength of thermo-plastics...

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