Abstract: Disclosed herein are microporous polybenzimidazole articles prepared by the addition of a leachable additive to a polybenzimidazole polymer solution or dope and the subsequent leaching of the additive from the polybenzimidazole article. The microporous polybenzimidazole article may be formed into filaments or films. The micropores of the microporous polybenzimidazole article may be filled with an absorbent resin which will act to absorb chemicals or other harmful products. The microporous polybenzimidazole article with absorbent material may be formed into clothing which is highly resistant to both chemicals and heat.

Abstract: The present invention provides a process for preparing microporous hollow fibers by solvent stretching a non-porous hollow precursor fiber having a controlled degree of molecular orientation as measured by birefringence. Control of the precursor fiber orientation, yields a microporous hollow fiber having an improved balance of mechanical strength and permeability.

Abstract: Halogenated hydrocarbons, such as 1,1,1-trichloro-2, 2-bis(chlorophenyl) ethane (DDT) and polychlorinated biphenyls (PCB), are removed from aqueous media including waste water from chemical manufacturing operations by contacting the aqueous media with an effective amount of a polyolefinic microporous adsorbent, preferably in the form of a filter or cartridge.

Abstract: The present invention provides an improvement in a "solvent stretch" process which renders it possible to transverse stretch a microporous film prepared from a precursor film which has been previously uniaxially stretched in a direction perpendicular to the intended transverse stretching direction to thereby improve the permeability of the microporous film while also improving the balance of mechanical properties thereof in both directions of stretch.The improvement lies in uniaxially stretching the precursor film to form a microporous film having a specifically defined permeability as measured by the Gurley test. The requisite permeability of the uniaxially stretched microporous film is obtained by selecting the polymer employed to prepare the precursor film based on certain specifically defined property requirements and by employing specifically defined process conditions during uniaxial stretching.

Abstract: Microporous films having improved morphological structure are prepared by the "solvent stretch" method from an olefinic precursor film having a controlled crystalline structure. The crystalline structure of the precursor film is controlled by preparing said film from an olefinic crystalline homopolymer characterized as having a melt index of about 3 to about 20 in the absence of a nucleating agent and a molecular weight distribution ratio of about 3.8 to about 13. In another embodiment the crystalline structure of the precursor film is controlled by incorporating a nucleating agent into the crystalline polymer resin from which the precursor film is prepared which thereby permits a reduction in the melt index of the polymer to about 0.3.

Abstract: A double acting metering pump is disclosed for use in apparatus to prepare matrices containing frangible particulate material. The double acting pump provides a metered output of matrix containing frangible particulate material which is mixed with a parent matrix from an extruding apparatus in a downstream static mixer. The pump includes pneumatically actuated valves that control the flow of matrix to each of two alternately discharged pumping chambers. The pump is facilely disassembled for cleaning and is surrounded by a heating jacket to maintain an essentially uniform temperature in the matrix during pumping.

Abstract: There is disclosed a process for preparing shear degradable particle-containing resin powders. This process comprises (a) preparing a first composition comprising shear degradable particles and molten resin in the absence of high shearing forces on the particles, (b) intimately blending the first composition with a second composition comprising molten resin and curing agent to form a shear degradable particle-containing molten resin mixture in the absence of high shearing forces on the shear degradable particles, (c) solidifying this shear degradable particle-containing molten resin mixture, and (d) grinding the solidified mixture to desired particle size. The particles may then be classified according to particle size.The final powder particles contain shear degradable particles or flakes in substantially undegraded form. The powder particles are especially useful in powder coating applications such as in automobile and appliance topcoats.

Abstract: An improved process is provided for producing a pyrolyzed carbonaceous filamentary material. The process utilizes a novel precursor of relatively high carbon content comprising a homogeneous blend of polystyrene and a substantial proportion of inexpensive pitch. Following melt spinning the resulting filamentary material is hot drawn, thermally stabilized, and carbonized. The thermal stabilization step of the process comprises the sulfonation of the previously hot drawn filamentary material. The thermally stabilized filamentary material optionally may be carbonized and graphitized. Processing difficulties commonly associated with a pitch precursor are effectively overcome.