Polysiloxane-polycarbonate

K. Glasgow and N. Alle, Transparent polymeric compositions comprising polysiloxane-polycarbonate copolymer, articles made therefrom and methods of making same, US Patent 7432327, assigned to SABIC Innovative Plastics IP B.V. (Bergen op Zoom, NL), October 7, 2008. 

Figure 3. Membrane efficiencies. Key MEM 213i polysiloxane/polycarbonate SSR, standard silicone rubber UTEFB, ultrathin ethyl cellulose perfluorobutyrate UTSR, ultrathin silicone rubber and BIOBLAND 16, polyCa-hexadecene sulfone). (Reproduced with permission from Ref. 12. Copyright 1976, Academic Press.)...

It is interesting to mention that the first truly synthetic (not based on natural products) polymer material was bakelite obtained in 1907 via polycondensation of phenol and formaldehyde. This material had good dielectric properties and was used mainly as an electrical insulator. The most famous polycondensation polymer is probably nylon belonging to the class of polyamides. Other common classes of polycondensation polymers are polyesters (like polyethylene terephthalate), polysiloxanes, polycarbonates, polysulfides, polyethers and polyimides. 

PL 5 pM gel mixed D 200 - 0.4 X 10 Resins, condensation polymers Polystyrene standard separation, resins, epoxy resin, polybutadiene, polysiloxane, polycarbonate... 

Finally, CarboSil and ChronoSil are thermoplastic polysiloxane/polycarbonate/ PU copolymers able to combine the mechanical strength of polycarbonate-based PUs with the biostability and hemocompatibihty of siloxane-based PUs. These products are also resistant to environmental stress aacking and therefore suitable for long-term cardiovascular applications. 

PEC is a high-heat polyestercarbonate shown in Figure 1, and PC-PDMS is a highly ductile polysiloxane-polycarbonate shown in Figure 2. Both resins are amorphous and transparent. In this study, it was postulated that blending PEC with PC-PDMS would create a product that would have a combination of heat, ductility, and transparency. 

Fig. 2. Molecular structures of selected photoconductive polymers with pendent groups (1) poly(A/-vinylcarba2ole) [25067-59-8] (PVK), (2) A/-polysiloxane carbazole, (3) bisphenol A polycarbonate [24936-68-3] (4) polystyrene [9003-53-6] (5) polyvin5i(l,2-/n7 j -bis(9H-carba2ol-9-yl)cyclobutane) [80218-52-6]...

The solubility of a solute in scC02 is extremely dependent on its structure, with three features of paramount importance. As expected, compounds of low polarity are more soluble than very polar compounds or salts. However, solubility also increases greatly with increasing vapour pressure of a substrate. To account for the contribution of volatility and solvation to the solubility process, Kurt Zosel coined the term Destraktion (from Latin destillare and extrahere) in his pioneering work on natural product extraction with SCFs [5], Finally, some specific functional groups like perfluoroalkyl and polysiloxane substituents, or polyether/polycarbonate copolymers... 

Boileau, S. Bouteiller, L. Khalifa, R. B. Liang, Y. Teyssid, D. Polycarbonate-Polysiloxane-Based Interpenetrating Networks. In Silicones and Silicone-Modified Materials-, Clarson, S. J., Fitzgerald, J. J., Owen, M. J., Smith, S. D., Eds. ACS Symposium Series 729 American Chemical Society Washington, DC, 2000 pp 383-394. 

Various properties (3,4,5,15,16,18-32) as well as the morphology ( L iJL, 19.,23 33) of such copolymers were investigated in great detail. Synthesis of these block copolymers, while complex, is potentially not costly since materials and methods used in the manufacturing of polysiloxanes and polycarbonates can be used. 

If this complex is sufficiently stable, then no further reaction occurs, and the polycondensation is obviated. However, as mentioned above, by using controlled monomer design, a variety of functionalised polymers (typical by with Mn = 10 000—30 000 and Mw/Mn = 2.0) can be synthesised polyethers [15,48 50], poly(thioether)s [48], polyesters [51,52], polycarbonates [53], polyketones [54], polysiloxanes [55-58], poly(carbosiloxane)s [59], poly(carbosilane)s [60], poly(carbodichlorosilane)s [61] and polymers with a conjugated % system [62]. 

Many of the remarks made in the previous section concerning fibres can be applied to the analysis of plastics. Some polymers are soluble in organic solvents and samples may be prepared for direct aspiration into a flame in this way, e.g. MIBK is a suitable solvent for polyesters, polystyrene, polysiloxanes, cellulose acetate and butyrate dimethyl formamide for polyacrylonitrile, dimethyl acetamide for polycarbonates and polyvinyl chloride cyclohexanone for polyvinyl chloride and polyvinyl acetate formic acid for polyamides and methanol for polyethers. These organic solutions may alternatively be injected into a graphite furnace. Otherwise, polymers may be wet or dry ashed and the resultant ash dissolved in acid. An approach which is attracting increasing interest is the direct insertion of solid samples into a graphite furnace. 

Linear polysiloxanes having reactive terminal groups are often condensed with reactive orgaiuc polymers. For example, hydroxy-terminated siloxanes can be condensed with a carboxy-terminated polyester, as illustrated in equation (28). The resulting polymers behave as thermoplastic elastomers, having some of the desirable properties of both siloxanes and polyesters. Similar condensation reactions have been used to synthesize siloxane copolymers with polyamides, polyethers, polycarbonates, and so on. 

A number of copolymers such as pol3 butylene terephtalate)-poly(tetramethylene terephtalate) polysuiphone-poly(dimethylsiloxane) polycarbonate-polysiloxane polyethylene-pol3 propylene and many others " have been synthetized and studied. However, the respective papers are mainly aimed at application, and we lall not analyze them in the present review. 

Figure 29. Representative time-of-flight signals for hole transport, a) tri-p-tolylamine (TTA) (30 wt.%) in polystyrene. (Reprinted with permission from Ref. [60b].) Two operational definitions of the transit time are indicated by t, and t /2. b) p-Diethylamino-benzaldehyde diphenylhydrazone (DEH) (30 wt. /o) in bisphenol-A polycarbonate. (Reprinted with permission from Ref. [60i].) c) A polysiloxane with A-alkylcarbazole pendant groups. (Reprinted with permission from Ref. [72g].)...

Nylon Polyalkylene Polystyrene Polyacrylates Polyacrylamide Polyethylene Polypropylene Polyvinyl alcohol Polyvinylacetate Polyvinylchloride Polyethylene glycol Polyester Polycarbonate Polyurethane Polysiloxane Phenol-formaldehyde Cellulose Starch Agarose Dextran Chitin Polyalginate Carrageenan Sand Pumice Metal oxides Diatomaceous earth Clays... 

Radiation-induced Degradation.—There have been several reports on radiation effects in polymers,288 including single crystals,287 fluoropolymers,288 polyamides,289 polysiloxanes,270 polyethylene and its copolymers,271 polypropylene,272 polyolefins,273 polystyrene and its copolymers,274 poly(vinyl chloride) and related polymers,275 rubbers,278 polysulphones and other sulphur-containing polymers,277 polycarbonate,278 nylon,279 poly(vinylpyridines),280 and wool.281... 

Polycarbonates Polyethylene Polymethyl Methacrylate Polypropylene Polysiloxane Polystyrene Polyurethane Polyvinyl Chloride Potassium Bicarbonate Potassium Bisulfate Potassium Bitartrate Potassium Hydroxide Propane Propylene Pyridoxine... 

Phosphoric Acid Polycarbonates Polymethyl Methacrylate Polysiloxane Polyurethane Potassium Bicarbonate Potassium Bisulfate... 

For example, the abrasion-resistant coatings based on a silicone-silica hybrid (33) have provided a scratch- and mar-resistant finish for polycarbonate as well as metals. The chemistry involved is discussed by Vincent, Kimball and Boundy (3iL). The coating consists of polysiloxane and silane-modified submicron silica particles, microscopically dispersed in the solution. The coating is then cured at elevated temperatures. Currently, this type of abrasion resistant coating is marketed in the U.S. by Dow Corning and General Electric Company. 

Step-growth polymerization is a very important method for the preparation of some of the most important engineering and specialty polymers. Polymers such as polyamides [7], poly(ethylene terephthalate) [8], polycarbonates [9], polyurethanes [10], polysiloxanes [11], polyimides [12], phenol polymers and resins, urea, and melamine-formaldehyde polymers can be obtained by step-growth polymerization through different types of reactions such as esterification, polyamidation, formylation, substitution, and hydrolysis. A detailed list of reaction types is shown in Table 3.2. 

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