Abstract:
The invention is directed to polyethylene foam based on a blend comprising 95.5-99.5% by weight low density polyethylene and 0.5-4.5% by weight high density polyethylene and a nucleating agent.The invention is also directed to a process for physical foaming of a blend comprising 95.5-99.5% by weight low density polyethylene and 0.5-4.5% by weight high density polyethylene in the presence of a physical blowing agent and a nucleating agent.
Abstract:
Foam a polymer blend of (a) a high melt strength polypropylene (HMS PP); (b) a linear or substantially linear polypropylene that has a melting point within ten degrees Celsius of (a), a melt flow rate that is significantly different than (a) and that is miscible with (a); and, optionally, (c) a polyethylene that is immiscible with (a) produces a polymeric foam having an average cell size of at least four millimeters and that has an inherent open-celled content of at least 40 percent. The HMS PP makes up 60 weight percent (wt %) or more and 90 wt % or less of the total combined weight of (a) and (b). Component (c) makes up 60 wt % or less of the total polymer blend weight.
Abstract translation:泡沫(a)高熔体强度聚丙烯(HMS PP)的聚合物共混物; (b)具有(a)熔点在10摄氏度内的线性或基本上线性的聚丙烯,熔体流动速率与(a)明显不同且与(a)混溶)。 和(c)与(a)不混合的聚乙烯,其产生具有至少四毫米的平均泡孔尺寸并且具有至少40%的固有的开孔含量的聚合物泡沫。 HMS PP占(a)和(b)的总组合重量的60重量%(wt%)以上且90重量%以下。 组分(c)占总聚合物共混物重量的60重量%或更少。
Abstract:
Disclosed is a flame-retardant styrene resin composition. The composition comprises 100 parts by weight of a styrene resin, 0.5 to 10 parts by weight of a brominated flame-retarder which has a bromine content of 60% by weight or higher, and 0.005 to 0.5 part by weight of urea, thiourea or an N-substituted derivative thereof. By using an urea compound concomitantly, the amount of the brominated flame-retarder required for achieving a desired flame retardancy level can be reduced.
Abstract:
The present invention provides a method for producing polylactic acid-based resin foamed particles for in-mold foam-molding from which a polylactic acid-based resin foam-molded article excellent in heat resistance and mechanical strength can be obtained by in-mold foam-molding. In the method of the present invention for producing polylactic acid-based resin foamed particles for in-mold foam-molding, a rotary blade is rotated at a given rotation speed while being always in contact with the front end surface of a nozzle and a polylactic acid-based resin extrudate extrusion-foamed through a nozzle is cut with the rotary blade, so that it is possible to cut the polylactic acid-based resin extrudate surely to obtain substantially spherical polylactic acid-based resin foamed particles. Therefore, when polylactic acid-based resin foamed particles are used for in-mold foam-molding, the polylactic acid-based resin foamed particles foam uniformly in all directions and, as a result, the foamed particles are thermal fusin bonded to unite together strongly in all direction.
Abstract:
Prepare a closed-cell alkenyl aromatic polymer foam by an extrusion process using a blowing agent composition that contains at least 30 weight-percent of the chlorine-free hydrofluorocarbon blowing agent such that the foam has a density of 48 kilograms per cubic meter or less, contains more than 50 weight-percent styrene-acrylonitrile copolymer based on total polymer weight and at least eight weight-percent of a chlorine-free hydrofluorocarbon blowing agent that has a lower solubility in polystyrene than 1,1,2,2-tetrafluoroethane (HFC-134).
Abstract:
A foamed sheet of a base resin containing 50 to 100% by weight of a polylactic acid resin and having an apparent density of 63 to 630 kg/m3, a thickness of 0.5 to 7 mm and endothermic and exothermic calorific values of ΔHendo:2 and ΔHexo:2, respectively, as measured by heat flux differential scanning calorimetry at a heating rate of 2° C./min. The endothermic calorific value ΔHendo:2 is at least 10 J/g and the difference (ΔHendo:2-ΔHexo:2) between the endothermic calorific value ΔHendo:2 and the exothermic calorific value ΔHexo:2 is more than 20 J/g and less than 40 J/g. A foam molding such as a receptacle is prepared by thermoforming the foamed sheet.
Abstract:
The present invention provides a shapeable resin-containing composition comprising at least one saccharide ester, preferably according to Formula I. wherein “A” is hydrogen or has the structure of Structure I: wherein “R” is an aliphatic or aromatic moiety of about eight to about 40 carbon atoms, and wherein at least one “A” moiety of Formula I is a moiety of Structure I. Also provided are shaping methods and shaped products based on the present compositions.
Abstract:
An extruded, low density, ethylenic polymer foam including from about 86% by volume to about 98% by volume open cells and a continuous, impervious surface skin is disclosed. The foam possesses superior compression recovery and lower compression resistance when compared with similarly comprised ethylenic closed cell foams and superior moisture resistance and handling characteristics when compared to open cell foams. A precursor composition and method for making the extruded, low density, ethylenic polymer foam are also disclosed.
Abstract:
Provided is a method of producing a microporous sheet material of a polymeric matrix of polyolefin, with finely divided and substantially water-insoluble filler distributed throughout the matrix, and a network of interconnecting pores communicating throughout the microporous material. The method includes: (a) forming a mixture of polyolefin, filler and a processing plasticizer composition; (b) extruding the mixture to form a continuous sheet; and (c) contacting the continuous sheet with a non-flammable extraction fluid composition to extract the processing plasticizer composition from the continuous sheet. The extraction fluid has a boiling point of 75° C. or less, and is essentially free of trichloroethylene. The microporous sheet material has Tensile Strength equal to or greater than 800 kPa. A microporous sheet material also is provided.
Abstract:
In accordance with an aspect of the invention, methods of forming medical articles are provided, which comprise (a) preparing a melt phase that comprises a molten polymer and a supercritical fluid, (b) forming a polymeric region from the melt phase, and (c) cooling the polymeric region. In certain embodiments, the supercritical fluid is formed from chemical species (e.g., CO2, propane, etc.) that are gases at room temperature (25° C.) and atmospheric pressure (1 atm). According to another aspect of the present invention, medical articles are provided which comprise melt-processed polymeric materials. The polymeric materials have a composition that cannot be melt processed without the use of melt-viscosity reducing additives due to thermal degradation, and yet the polymeric material does not contain such additives.