摘要:
Flame retardant polymeric blend compositions including a synergistic combination of flame retardants, including a halogenated flame retardant and a nanoparticulate, such as an organically modified clay or a natural nanoclay. The compositions are thermoplastic elastomers, include a polyolefin and a styrenic block copolymer, and exhibit high char formation upon burning as well as desirable vertical burn characteristics. In a preferred embodiment, the flame retardants include at least a halogenated flame retardant and a metal oxide.
摘要:
Flame retardant polymeric blend compositions including a synergistic combination of flame retardants, including a halogenated flame retardant and a nanoparticulate, such as an organically modified clay or a natural nanoclay. The compositions are thermoplastic elastomers, include a polyolefin and a styrenic block copolymer, and exhibit high char formation upon burning as well as desirable vertical burn characteristics. In a preferred embodiment, the flame retardants include at least a halogenated flame retardant and a metal oxide.
摘要:
A compatibilizer including a first portion compatible with a fluoropolymer and a second portion compatible with a polyolefin. Compatibilized compositions comprising a polyolefin, a fluoropolymer, and a compatibilizer are also disclosed. Methods for forming both the compatibilizer and the blends contained in the compatibilizer are described. The compatibilized compositions of the present invention exhibit desired mechanical properties such as tensile strength and elongation. The flame retarded compatibilized blends exhibit desirable dielectric properties, are flame resistant and exhibit low smoke emission.
摘要:
A method for polymerizing at least one unsaturated monomer in the presence of a latex results in a high solids dispersion of polymer particles with lower viscosities than traditionally observed. A significant wt. % of the polymer from added monomers can be present in large particles, having nonspherical shapes. Some of the original latex particles are retained during the polymerization and these increase the solids content and lower the viscosity by packing in the interstices between large particles. The total polymer solids content can easily be varied from 70 to 92 or more wt. %. The viscosities at very high solids contents become paste-like but the materials still are stable to storage and further handling without causing the dispersion to separate into an agglomerated polymer portion and released water. The dispersions are useful to form sealants, membranes, etc., either with or without other additives. A preferred use is as an acrylate water-based caulking compound where the high solids and thixotropy of the dispersion allows for formation of a water-based caulk with low shrinkage.
摘要:
Various processing advantages are gained when ultrasonic vibration is applied to a thermoplastic processing apparatus such as an extruder or an injection molding device. Such advantages include improved flow rate, reduced processing pressure, and consequently reduced processing temperature to mold or extrude the melted thermoplastic. The ultrasonic vibration is desirably applied to the die of the processing apparatus and in a direction longitudinal to the flow of the thermoplastic. Suitable thermoplastics include polystyrene and polyolefins.
摘要:
Shaped articles which have excellent solvent resistance and resistance to fatty acids are formed from a thermoplastic polyblend of poly(vinyl chloride) (PVC), chlorinated polyethylene (CPE), polyolefin (PO), and a graft copolymer of a polyolefin (PO-G). The thermoplastic polyblend contains a PO and PO-G (PO/PO-G) as a first continuous single phase, PVC and CPE as the second and third dispersed phases, and the relative amounts of the components are chosen so that there is, at most, an equal amount by weight of PO and PO-G each of which may be present in an amount as high as 40 parts by weight when the PVC is present in an amount in the range from 40 to 70 parts, so as to provide a mechanically compatible polyblend without miscibility or chemical compatibility. Further, a glass fiber reinforced (GFR) polyblend of PVC/CPE/PO/PO-G having a HDT of at least 95.degree. C. and sufficient thermoformability to form the desired article has excellent notched impact strength. In the GFR polyblend the fibers are preferably long, at least 3 mm, and from 10-20 microns in diameter. The high HDT is obtained provided only if both co-compatibilizers and glass fibers are present in the reinforced composite.
摘要:
Soft flame retardant thermoplastic compositions that are preferably halogen free and include a styrenic block copolymer having a low modulus, one or more of a polyolefin polymer or copolymer and an acrylate containing polymer or copolymer, one or more of a softener and plasticizer, an inorganic phosphorous-containing flame retardant, and optionally but preferably, a platelet filler such as a nanoclay or an organic modified clay. In a preferred embodiment, the phosphorous-containing flame retardant has a surface coating thereon which reduces sensitivity of the flame retardant to water, and thus reduces the amount of the flame retardant that can leach out in the presence of water, thereby enabling the compositions of the present invention to be utilized outdoors or other environments where exposure to water or high humidity is possible. The hardness of the compositions according to the invention preferably ranges from about Shore A 40 to about Shore A 90. The compositions exhibit high char formation upon burning and also desirable vertical burn characteristics.
摘要翻译:软阻燃热塑性组合物优选无卤素,并且包括具有低模量的苯乙烯嵌段共聚物,聚烯烃聚合物或共聚物中的一种或多种,含丙烯酸酯的聚合物或共聚物,软化剂和增塑剂中的一种或多种,无机磷 含有阻燃剂,以及任选但优选为片状填料,例如纳米粘土或有机改性粘土。 在优选的实施方案中,含磷阻燃剂在其上具有表面涂层,其降低了阻燃剂对水的敏感性,从而减少了在水存在下可以浸出的阻燃剂的量,从而使得 本发明要在户外或其他暴露于水或高湿度的环境中使用。 根据本发明的组合物的硬度优选在约Shore A 40至约Shore A 90的范围内。该组合物在燃烧时表现出高的焦炭形成性,并且还具有期望的垂直燃烧特性。
摘要:
A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, a useful powder is disclosed that has a two-tier distribution in which substantially no primary particles have an average diameter greater than 180 μm, provided further that the number average ratio of particles smaller than 53 μm is greater than 80%, the remaining larger particles being in the size range from 53 μm to 180 μm. A powder with slow recrystallization rates, as evidenced by non-overlapping or slightly overlapping endothermic and exothermic peaks in their differential scanning calorimetry characteristics for scan rates of on the order of 10° C. to 20° C. per minute, will also result in sintered parts that are near-fully dense, with minimal dimensional distortion.
摘要:
Alloys of polycycloolefin polymers are produced by dissolving an ethylene-based functional polymer in at least one polycycloolefin monomer and polymerizing the mixture. Various polycycloolefin catalysts can be utilized. Often it is desirable to utilize bulk polymerization including reaction injection molding (RIM), liquid injection molding (LIM), reinforced reaction injection molding (RRIM), resin transfer molding (RTM), and the like. The alloys have improved properties such as impact strength, solvent resistance, as well as improved thermal aging properties such as retention of impact strength.
摘要:
A rubber composition having improved green strength is made by mixing chemically similar blends together and forming a heterogeneous blend. Generally, one of the blends called a minor fraction has a smaller amount of the primary components therein such as rubber and carbon black.