Showing papers on "Polycarbonate published in 1971"

Process for providing uniform organopolysiloxane coatings on polycarbonate and acrylic surfaces

Abstract: PROCESS, AND THE ARTICLE PRODUCED THEREBY, FOR PROVIDING A UNIFORMLY AND TENACIOUSLY ADHERED, HARD, ACETONE-RESISTANT AND MAR-RESISTANT COATING ON ARTICLES HAVING A SOLID POLYCARBONATE OR ACRYLIC SURFACE. THE PROCESS INCLUDES PRIMING THE POLYMERIC SURFACE WITH AN ADHESION PROMOTING, THERMOSETTABLE ACRYLIC BY FORMING A THIN FILM THEREON, THEN COATING THE PRIMED SURFACE WITH A SOLUTION OF A PRECURED SOLVENT-SOLUBLE, FURTHER-CURABLE ORGANOPOLYSILOXANE IN AN ORGANIC SOLVENT AND THEREAFTER EVAPORATING THE SOLVENT AND FINALLY CURING THE ORGANOPOLYSILOXANE TO A THERMOSET CONDITION. THE SOLVENT-SOLUBLE, FURTHER-CURABLE ORGANOPOLYSILOXANE IS PRODUCED BY HEATING METHYLTRIALKOXYSILANE, PHENYLTRIALKOXYSILANE OR MIXTURES THEREOF AND WATER IN THE PRESENCE OF AN EFFECTIVE CATALYTIC AMOUNT OF A HYDROLYSIS CATALYST, E.G., HCL, AT A SUFFICIENT TEMPERATURE AND FOR A TIME SUFFICIENT TO FORM A PARTIAL CONDENSATION PRODUCT, CONCENTRATING THIS PRODUCT BY HEATING TO REMOVE SOME ALKANOL BY-PRODUCT AND WATER AND THEREAFTER PRECURING THE PRODUCT BY HEATING BELOW THE GEL POINT THEREOF.

Transparent impact resistant poly(carbonate-urethane)laminates

Abstract: LAMINATES FOR USE AS AUTOMOBILE WINDSHIELDS OR OTHER SAFTEY GLASS APPLICATIONS COMPRISING A POLYCARBONATE URETHANE AND ONE OR MORE SHEETS OF GLASS ARE PROVIDED. THE URETHANE IS PREFERABLY A THERMOPLASTIC MATERIAL FORMED FROM AN ALIPHATIC POLYCARBONATE, A CYCLOALIPHATIC DIISOCYANATE AND A MONOMERIC ALIPHATIC DIOL.

Flame retardant compounds and thermoplastic compositions containing the same

Abstract: There are provided low molecular weight poly(halogenated dihydrid phenol carbonates), which are efficient flame retardant agents for flammable thermoplastic resins, including those with high ignition temperatures. Illustratively, aromatic polycarbonate, poly-(alkylene terephthalate), acrylonitrilebutadiene-styrene, and polyphenylene ether thermoplastic resins are rendered self-extinguishing by incorporation of a low molecular weight polymer of a carbonate of tetrabromobisphenol-A, chain-stopped with tribromophenol.

Polycarbonate molding compositions having improved release properties containing an ester of a trihydric alcohol and a c-10 to c-22 saturated aliphatic carboxylic acid

Abstract: POLYCARBONATE MOLDING COMPOSITIONS ARE PROVIDED WHICH CONTAIN FROM ABOUT 0.1 TO ABOUT 2% BY WEIGHT BASED ON THE WEIGHT OF THE POLYCARBONATE OF ONE OR MORE ESTERS OF TRIHYDRIC ALCOHOLS AND SATURATED ALIPHATIC CARBOXYLIC ACIDS CONTAINING FROM TEN TO TWENTY-TWO CARBON ATOMS.

Method for stabilizing pigmented polycarbonate resins

Abstract: A method is provided for stabilizing polycarbonate resin tinted with ultramarine pigment, involving the incorporation of the ultramarine pigment into the polycarbonate resin as an arylsiloxane-pigment blend. There also is employed with the arylsiloxane-pigment blend, polycarbonate resin stabilizers such as triorganophosphite, and a cyclo aliphatic epoxy compound. The stabilized resin can be remolded without a significant increase in the Yellow Index of the resin.

On the solvent stress‐cracking of polycarbonate

Abstract: The stress-cracking of polycarbonate by a gaseous or liquid agent results from the diffusion of this agent into the polymer. The low molecular weight polymer fractions and the chain ends within the bulk of the polymer become more ordered during the diffusion and swelling process by their partial solubility in the crazing agent, causing crystallization. The creation of interfaces at areas of order-disorder causes high shearing forces at this boundary and voids within the bulk of the polymer. These voids are then propagated as crazes or cracks at stresses much lower than the tensile strength of the polymer. Therefore, a stress-cracking agent need not diffuse rapidly, but must be an effective environment for swelling and/or crystallization. Data from diffusion, density, thermal and molecular analyses are presented to support this mechanism.

Thermally stable polycarbonate composition

Abstract: A polycarbonate composition consisting of an aromatic polycarbonate with 0.1 to about 2.0 weight percent of an alkaline earth carbonate and a mixture of an organosiloxane polymer and a polytetrafluoroethylene. The amounts of the organosiloxane polymer and polytetrafluoroethylene may be present in an amount of 0.1-2.0 weight percent each based on the weight of the polycarbonate. More specifically, the alkaline earth carbonate which can be employed herein is barium carbonate.

Transition from linear to nonlinear viscoelastic behavior. Part II. stress relaxation of polycarbonate

Abstract: Below the glass transition temperature Tg (ca. 150° C), the vis-coelastic behavior of the polycarbonate of bisphenol A is linear up to a strain level of about 1%, whereas, at higher strains, the iso-chronous relaxation modulus drops steadily with increasing strain. The critical strain level diminishes from about 1.2 to about 0.7% as the temperature of glassy polycarbonate increases from 23° to 130° C. Comparison of this finding with earlier independent observations above Tg indicates rather unexpectedly that, in terms of the strain level alone, linear viscoelasticity theory should be minimally applicable near Tg. These conclusions emerge from a detailed study of stress relaxation at constant uniaxial strain performed on amorphous, elastically isotropic specimens of this polycarbonate.

High temperature membrane materials

Abstract: BLOCK COPOLYMERS OF POLYDIORGANOSILOXANE AND POLYCARBONATE ARE PROVIDED HAVING IMPROVED HEAT DISTORTION AND USEFUL AS HIGH TEMPERATURE MEMBRANE MATERIAL. THE POLYDIORGANOSILOXANE-POLYCARBONATE BLOCK COPOLYMER MEMBRANES CAN BE STEAM STERILIZED AT LEEVATED TEMPERATURES WITHOUT ALTERING MEMBRANE STRUCTURE. A METHOD FOR MAKING SUCH BLOCK COPOLYMERS ALSO IS PROVIDED UTILIZING CERTAIN DIHYDRIC PHENOLS DERIVED FROM CYCLIC KETONES SUCH AS FLUORENYL BISPHENOLS, TO MAKE THE POLYCARBONATE BLOCKS.

Ion-specific membrane

Abstract: AN ION-SPECIFIC MEMBRANE INCLUDES A HYDROPHOBIC ELASTOMERIC POLYMER WITH A DIELECTRIC CONSTANT OF 4 TO 13, AND AN ION-SPECIFIC CARRIER. THE HYDROPHOBIC ELASTOMERIC POLYMER IS PREFERABLY AN ORGANOPOLYSILOXANE POLYCARBONATE BLOCK COPOLYMER. THE ION-SPECIFIC CARRIERS INCLUDE H+ AND K+ ION CARRIERS.

Thermal analyses of polymers. VII. Calorimetric and dilatometric aspects of the glass transition

Abstract: For the determination of Tg by DTA with the use of small samples, slow heating rates, and extrasensitive amplification, it can be shown that the previously reported basel ne changes for polystyrene, polychloroprene, poly(methyl methacrylate), and polycarbonate can be resolved as endotherms. Measurements with small samples more accurately determine the calorimetric changes than with large samples, even at slow heating rates. The use of large samples for DSC or DTA measurements may be the reason for apparent heating rate dependence. The measurements of this study indicate little heating rate dependence if very small samples are used. Moreover, the slower the cooling from the melt, the sharper the endotherms, indicating the importance of thermal history. The data raise the question about the validity of assuming that a baseline or abrupt change in Cp via a DTA measurement is necessarily that of a real second-order change or Tg. Preliminary dilatometric results tend to show that the changes for polystyrene, polychloroprene, poly(methyl methacrylate), and polycarbonate may be first order at 94°C, 32°, 114°, and 156°C, respectively. Only the change at 75°C for polystyrene appears second order by volume—temperature data.

Transport of sulphur dioxide in polymers

Abstract: Studies were made of the permeation, solution, and diffusion of sulphur dioxide in polyethylene, polyamide (Nylon 11), and polycarbonate at 25 °C and at pressures up to one atmosphere. The steady-state permeability coefficients of sulphur dioxide in all three polymers were pressure-dependent, and the effect of pressure on the solution and diffusion processes, which together govern the overall permeation process, account for the observed relations. Solution and diffusion in the two glassy polymers, polyamide and polycarbonate, were strongly pressure-dependent whereas in polyethylene diffusion was pressure-dependent but solution obeyed Henrys law. The vapour pressure isotherms of the glassy polymers obeyed a modified Langmuir expression suggesting that two concurrent sorption mechanisms were operative, the filling of microvoids within the polymer structures and ordinary Henrys law solution. Kinetic sorption-desorption studies showed that diffusion was “Fickian” in polyethylene and polyamide over the entire pressure range. It was also “Fickian” in polycarbonate at pressures up to approximately 25 cm Hg, but “non-Fickian” at higher levels. For each polymer, diffusion coefficients were determined by steady-state permeation and transient sorption-desorption methods, and the separate methods gave similar values.

Polycarbonate modified polyesters of reduced carboxyl groups

Abstract: A PROCESS IS DISCLOSED AND CLAIMED WHICH PROVIDES FOR THE LATE ADDITION OF A POLYCARBONATE TO A FIBER-FORMING POLYESTER METAL WHICH RESULTS IN A POLYESTER HAVING A LOWER LEVEL OF CARBOXYL END GROUPS. THE IMPROVED POLYESTER OF THIS INVENTION EXHIBITS UTILITY IN REINFORCED RUBBER ARTICLES SUCH AS INDUSTRIAL BELTS AND PNEUMATIC TIRE STRUCTURES.

Fractionation and characterisation of bisphenol a polycarbonate by gel permeation chromatography

Abstract: Bisphenol A polycarbonate was fractionated from methylene chloride solution by a progressive precipitation technique. The intrinsic viscosities of these fractions were obtained in methylene chloride solution and corresponded to a viscosity average molecular weight range of 2 × 103 to 80 × 103. The fractions were used to calibrate a gel permeation chromatograph, an experimental Q-factor of 23.8 was found. The calibration was further confirmed by membrane osmometry and light scattering experiments. The experimental viscosity data demonstrated that the Kurata-Stockmayer-Roig relationship is suited to interpret the molecular expansion of polycarbonate in methylene chloride.

Thermal oxidatively stable polycarbonate composition

Abstract: A thermal oxidatively stable polycarbonate composition consisting of the reaction product of bisphenol-A, a carbonate precursor and a minor amount of phosphorus dihalide, the composition having in admixture therewith a particular epoxidized composition in an amount of 0.01 to about 1.0 weight percent wherein the epoxy composition may be an epoxidized cycloaliphatic compound. The formula of the epoxy composition is as follows:

Press polishing curved transparent polycarbonate sheet material

Abstract: AN IMPROVED METHOD OF PRESS POLISHING TRANSPARENT POLYCARBONATE SHEET MATERIAL BETWEEN COMPLEMENTARY SHAPED, OPTICALLY SMOOTH SURFACES OF PRESS POLISHING MEMBERS THAT HAVE SHAPES CONFORMING TO THE SHAPE DESIRED FOR THE TRANSPARENT POLYCARBONATE SHEET INVOLVING TIMELY SEPARATION.

Process for the production of polycarbonate solutions

Abstract: The invention is related to the production of the solution of a high molecular weight polycarbonate having a molecular weight above 30,000 suitable for the production of films and filaments. The process comprises subjecting the solid polycarbonates solutions obtained by solvent removal from polycarbonate solutions at temperatures below the melting point of said polycarbonate coupled with the application of shear energy for 0.1 to 50 hours to a solvent atmosphere of solvents which are able to dissolve polycarbonates and subsequently redissolving the thus obtained products.

Method of controlling reaction of polyisocyanate with polyamine

Abstract: THIS INVENTION RELATES TO A METHOD OF MAKING POLYURETHANE HAVING IMPROVED RESISTANCE TO DICOLORATION, FOR INSTANCE, IN A WEATHEROMETER FOR 100 HOURS. THESE POLYURETHANES ARE PREPARED BY REACTING A REACTIVE HYDROGEN CONTAINING MATERIAL SUCH AS POLYESTERS, POLYETHERS, POLYESTER AMIDES, CASTOR OIL, POLYCARBONATE POLYOLS AND POLYDIENE POLYOLS AND THE HYDROGENATED POLYDIENE POLYOLS WITH A NONAROMATIC ORGANIC POLYISOCYANATE AND A NONAROMATIC PRIMARY DIAMINE IN THE PRESENCE OF SUFFICIENT INERT SOLVENT TO RENDER THE MIXTURE SPREADABLE.

Polyamide in combination with polycarbonate, metal complex, polyisocyanating agent for polyester modification and rubber tire structures made therefrom

Abstract: Relates to an improved rubber structure reinforced with an improved polyethylene terephthalate reinforcing fiber modified with a polyamide in combination with a metal complex or this two-component combination in combination with a polycarbonate, or the polyamide in combination with a polycarbonate and a polyisocyanating agent, the modifier being present with the polyester prior to fiber formation.

Method for stabilizing polycarbonates and compositions made thereby

Abstract: A METHOD IS PROVIDED FOR IMPROVING THE RESISTANCE OF POLYCARBONATE RESINS TO YELLOWING, RESULTING FROM MOLDING THE RESIN AT TEMPERATURES BETWEEN 500*F.-700*F. THERE IS UTILIZED AN EFFECTIVE AMOUNT OF AN ORGANOSILICON HYDRIDE SUCH AS TRIHEXYLSLANE. THERE ALSO IS PROVIDED POLYCARBONATE COMPOSITIONS MADE BY SUCH METHOD EXHIBITING STABILITY TOWARD COLOR CHANGE DURING MOLDING AND SUBSEQUENT FABRICATION.

Plane Bending Fatigue of Glass Fiber Reinforced Polycarbonate

Abstract: ポリカーボネイト樹脂に不連続ガラス短繊維を混入したガラス繊維強化ポリカーボネイト樹脂に, 定荷重両振り平面曲げ疲労を与え, 疲労強度および疲労き裂伝ばに及ぼすガラス繊維の影響を調べた。その結果, 疲労破壊強度はガラス繊維を混入すると増大する。ガラス繊維を含む試料は, ガラス繊維端のmicrocrackの発生からき裂が進展し, 試料端から発生した主き裂と連なって進展するため, ガラス繊維を含まない試料にくらべ, 含有率が増加するほどき裂進展速度は減少することが明らかとなった.疲労破面のガラス繊維による影響をフラクトグラフィックに観察した結果, その破面のパターンに変化があったことからガラス繊維の阻止効果が認められた。

Effects of molding temperatures on aqueous fatigue behavior of polycarbonate: Investigation shows that fatigue strength of injection-molded polycarbonate is strongly dependent on specimen geometry and processing variables

Abstract: Fatigue behavior of polycarbonate was investigated to evaluate its potenitial as a material for prosthetic heart valves. Smooth and notched small cantilever specimens were injection molded using various combinations of cylinder and mold temperates. Fatigue testing was conducted in a machine specifically designed to accommodate multipe specimens inliquid environments. Results presented herein are for water immersion. The fatigue lives fell on Weibull distributions with nonzero minimum-life parameters. S-N equations were fitted at constant probabilities of failure; most of these had nonzero fatigue-limit parameters. Polycarbonate fatigue strengths, of notched spcimens particularly, were greatly influenced by cylinder and mold temperatures. Notch sensitivities varied from very low to quite high. These effects were attributed to molecular orientation and residual stresses.