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Polycarbonates polystyrene carbonate

Another serious effect occurs with liquids which are not in themselves solvents but which may wet the polymer surfaces. These facilitate relief of frozen-in stresses by surface cracking which can be a severe problem in using many injection and blow mouldings with specific chemicals. Examples of this are white spirit with polystyrene, carbon tetrachloride with polycarbonates and soaps and silicone oils with low molecular weight polyethylenes. [Pg.922]

Epoxides can co-polymerize with CO2 to give aliphatic polycarbonates. The co-polymerization is one of the most promising methods to utilize GO2 as a Cl feedstock. The product polycarbonates have many potential applications because of their unique properties. For example, poly(propylene carbonate) (PPG) decomposes completely at 300 °G in any environment to leave a very small amount of ash. This feature makes it applicable to pore former for mesoporous carbon composites. Poly(cyclohexene carbonate) (PGG) has glass-transition temperature (Tg) of 115°G, higher than 35-40 °G of PPG, endowing the materials with properties very similar to polystyrene. ... [Pg.609]

Although a majority of these composite thermistors are based upon carbon black as the conductive filler, it is difficult to control in terms of particle size, distribution, and morphology. One alternative is to use transition metal oxides such as TiO, VO2, and V2O3 as the filler. An advantage of using a ceramic material is that it is possible to easily control critical parameters such as particle size and shape. Typical polymer matrix materials include poly(methyl methacrylate) PMMA, epoxy, silicone elastomer, polyurethane, polycarbonate, and polystyrene. [Pg.596]

We have tested the following polymers polycarbonate (PC), poly-carbonate/4% polyethylene blend (PC/PE), poly (ethylene terephthal-ate) (PET), ABS, and impact modified polystyrene (HIPS). All materials except PC were compression molded into nominal Vs-inch sheets. The PC used was an Vs-inch extruded sheet heat-treated in a manner previously described (22). These PC specimens were considered to be... [Pg.107]

Another example is thermally depolymerizable polycarbonates that are sensitized with onium salt cationic photoinitiators (139). As discussed previously (Section 3.2.3), one of the positive-negative resists based on polystyrene with pendant tertiary butyl carbonate protecting groups undergoes acid-catalyzed thermolysis to generate poly( p-vinylphenol), carbon dioxide, and isobutene. Therefore, if the tertiary butyl carbonate moiety is incorporated in the polymer backbone as a repeating unit, such polymers will... [Pg.171]

Tphe surface activity of block copolymers containing dimethylsiloxane units as one component has received considerable attention. Silicone-poly ether block copolymers (1,2,3) have found commercial application, especially as surfactants in polyurethane foam manufacture. Silicone-polycarbonate (4, 5), -polystyrene (6, 7), -polyamide (8), -polymethyl methacrylate (9), and -polyphenylene ether (10) block copolymers all have surface-modifying effects, especially as additives in other polymeric systems. The behavior of several dimethylsiloxane-bisphenol A carbonate block copolymers spread at the air—water interface was described in a previous report from this laboratory (11). Noll et al. (12) have described the characteristics of spread films of some polyether—siloxane block co-... [Pg.347]

In the flow cell, the test surfaces were exposed to the flowing solutions under well characterized flow conditions. Carbon, polystyrene, and polycarbonate surfaces were exposed to the flowing (135/sec. shear rate), dilute (100 micrograms/ml.) solutions of intact native human fibrinogen, human fibrinogen with the alpha chain... [Pg.54]

In blow molding, a tube of molten plastic material, the parison, is extruded over an apparatus called the blow pipe and is then encased in a split mold. Air is injected into this hot section of extruded stock through the blow pipe. The stock is then blown outward, where it foUows the contour of the mold. The part is then cooled, the mold opened, and the molded part ejected. In very heavy sections, carbon dioxide or Uquid nitrogen may be used to hasten the cooling. This process is widely used in molding high- and low-density polyethylene, nylon, polyvinyl chloride (PVC), polypropylene, polystyrene, and polycarbonates. [Pg.1325]

Polycarbonate bisphenol-A carbon dioxide and polystyrene 1997KAT... [Pg.107]

PC 100 Series. See Polyaluminum chloride PC-325. See Calcium carbonate PC1100 Siiane. See Aminopropyltriethoxysilane PC-1100. See Polycarbonate PC-1244] PC-1344. See Ethyl acrylate/2-ethylhexylacrylate copolymer PC 2065. See Polystyrene PC-2120. See Polyquatemium-6 PC3100 Siiane. See3-Glycidoxypropyltrimethoxysilane PC4100 Siiane. See3-Methacryloxypropyltrimethoxysilane PCA... [Pg.3049]

Chains of identical groups of atoms based on carbon with other elements, such as hydrogen and oxygen Colourless, when pure May be transparent. For example, polystyrene, polycarbonates... [Pg.15]

Phenolics, epoxies, polycarbonate, ABS Polyethylene, polypropylene, fluorocarbon, polyphenylene sulfide, polyolefin, thermoplastic polyester, polyphenylene ether, polystyrene, polycarbonate (glass or carbon fiber)... [Pg.617]

A candidate blend mentioned earlier is PC-PS, but this is not a practical proposition since the components of this blend are known to be incompletely miscible. However, the polycarbonate modified by incorporation of four methyl groups in the bisphenol-A moiety (ortho to the carbonate oxygen) is known to be compatible with polystyrene, and both polymers have approximately the same absolute value of Cor- The tetra-methyl polycarbonate used In the study by Werumeus Buning and Gijsen (12) was again made available by Bayer. [Pg.343]


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See also in sourсe #XX -- [ Pg.125 ]




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Polystyrene carbonate

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