The ultrahigh-molecular-weight polyethylene powder of the present invention is an ultrahigh-molecular-weight polyethylene powder having a viscosity-average molecular weight Mv of 10×10.sup.4 or higher and 1000×10.sup.4 or lower, wherein viscosity-average molecular weight Mv(A) of a kneaded product obtained by kneading under specific kneading conditions, and the Mv satisfy the following relationship: “{Mv−Mv(A)}/Mv is 0.20 or less”, and the ultrahigh-molecular-weight polyethylene powder contains an ultrahigh-molecular-weight polyethylene powder having a particle size of 212 μm or larger, wherein the powder having a particle size of 212 μm or larger has an average pore volume of 0.6 ml/g or larger and an average pore size of 0.3 μm or larger.

A dual-cure method for forming a solid polymeric structure is provided. An end-capped, imide-terminated prepolymer is combined with at least one photopolymerisable olefinic monomer, at least one photoinitiator, and a diamine, to form a curable resin composition, which, in a first step, is irradiated under conditions effective to polymerize the at least one olefinic monomer, thus forming a scaffold composed of the prepolymer and the polyolefin with the diamine trapped therein. The irradiated composition is then thermally treated at a temperature effective to cause a transimidization reaction to occur between the prepolymer and the diamine, thereby releasing the end caps of the prepolymer and providing the solid polymeric structure. A curable resin composition comprising an end-capped, imide-terminated prepolymer, at least one photopolymerisable olefinic monomer, at least one photoinitiator, and a diamine, is also provided, as are related methods of use.

A dual-cure method for forming a solid polymeric structure is provided. An end-capped, imide-terminated prepolymer is combined with at least one photopolymerisable olefinic monomer, at least one photoinitiator, and a diamine, to form a curable resin composition, which, in a first step, is irradiated under conditions effective to polymerize the at least one olefinic monomer, thus forming a scaffold composed of the prepolymer and the polyolefin with the diamine trapped therein. The irradiated composition is then thermally treated at a temperature effective to cause a transimidization reaction to occur between the prepolymer and the diamine, thereby releasing the end caps of the prepolymer and providing the solid polymeric structure. A curable resin composition comprising an end-capped, imide-terminated prepolymer, at least one photopolymerisable olefinic monomer, at least one photoinitiator, and a diamine, is also provided, as are related methods of use.

Embodiments are directed to a method of making an olefin-based polymer by free-radical polymerization in a reactor system. The method includes initiating a free-radical polymerization of an olefin-based monomer, propagating growth of the olefin-based polymer during continued free-radical polymerization of the olefin-based monomer, and adding to the reactor system a chain transfer agent that terminates the growth of the olefin-based polymer. The chain transfer agent includes a silane. Examples of suitable silanes are: triethylsilane, diethylmethylsilane, tris(trimethylsilyl)silane, n-butylsilane, dimethylphenylsilane, phenylsilane, chlorodimethylsilane, diisopropylaminosilane, 1,2-bis(dimethylsilyl) benzene, 1,3-bis(dimethylsilyl) benzene, 1,4-bis(dimethylsilyl)benzene, 1,1, 3,3-tetramethyldisiloxane, trimethylsilane, (trimethylsilyl)dimethylsilane, and bis(trimethylsilyl)methylsilane.

Embodiments are directed to a method of making an olefin-based polymer by free-radical polymerization in a reactor system. The method includes initiating a free-radical polymerization of an olefin-based monomer, propagating growth of the olefin-based polymer during continued free-radical polymerization of the olefin-based monomer, and adding to the reactor system a chain transfer agent that terminates the growth of the olefin-based polymer. The chain transfer agent includes a silane. Examples of suitable silanes are: triethylsilane, diethylmethylsilane, tris(trimethylsilyl)silane, n-butylsilane, dimethylphenylsilane, phenylsilane, chlorodimethylsilane, diisopropylaminosilane, 1,2-bis(dimethylsilyl) benzene, 1,3-bis(dimethylsilyl) benzene, 1,4-bis(dimethylsilyl)benzene, 1,1, 3,3-tetramethyldisiloxane, trimethylsilane, (trimethylsilyl)dimethylsilane, and bis(trimethylsilyl)methylsilane.

The present invention relates to thermally conductive materials, including, for instance, thermally conductive tubing and thermally conductive apparel, and applications thereof. In particular, the invention relates to thermally conductive tubing that can used in thermoregulatory apparel, such as, for example, cooling garments and cooling vests. In at least one embodiment, the present invention includes a thermally conductive material made from one or more base polymers and one or more additives that increase the thermal conductivity of the thermally conductive material relative to the one or more base polymers. The base polymer may include, for example, ethylene vinyl acetate (EVA), and the additive may include, for example, graphite fibers. The thermally conductive material may also include, for instance, a secondary polymer, such as ethylene propylene diene monomer (EPDM) and/or a plasticizer, such as bis(2-ethylhexyl) adipate (DEHA). Thermally conductive material produced according to one or more embodiments of the present invention may also be extruded or formed to create thermally conductive tubing and/or sheets.

The present invention relates to thermally conductive materials, including, for instance, thermally conductive tubing and thermally conductive apparel, and applications thereof. In particular, the invention relates to thermally conductive tubing that can used in thermoregulatory apparel, such as, for example, cooling garments and cooling vests. In at least one embodiment, the present invention includes a thermally conductive material made from one or more base polymers and one or more additives that increase the thermal conductivity of the thermally conductive material relative to the one or more base polymers. The base polymer may include, for example, ethylene vinyl acetate (EVA), and the additive may include, for example, graphite fibers. The thermally conductive material may also include, for instance, a secondary polymer, such as ethylene propylene diene monomer (EPDM) and/or a plasticizer, such as bis(2-ethylhexyl) adipate (DEHA). Thermally conductive material produced according to one or more embodiments of the present invention may also be extruded or formed to create thermally conductive tubing and/or sheets.

Methods of preparing oligomers of an olefin are provided. The methods can include providing an alkylaluminum compound and irradiating the alkylaluminum compound with microwave radiation to provide an irradiated alkylaluminum compound. The methods can further include mixing the irradiated alkylaluminum compound with a chromium compound, a pyrrole compound, and a zinc compound to provide a catalyst composition. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

Methods of preparing oligomers of an olefin are provided. The methods can include providing an alkylaluminum compound and irradiating the alkylaluminum compound with microwave radiation to provide an irradiated alkylaluminum compound. The methods can further include mixing the irradiated alkylaluminum compound with a chromium compound, a pyrrole compound, and a zinc compound to provide a catalyst composition. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

The present invention provides a process for the preparation of a multimodal polyethylene comprising: (i) polymerising ethylene and optionally an α-olefin comonomer in a first polymerisation stage to produce a first ethylene polymer; and (ii) polymerising ethylene and optionally an α-olefin comonomer, in the presence of said first ethylene polymer, in a second polymerisation stage, wherein the first and second polymerisation stages are carried out in the presence of an unsupported metallocene catalyst and each polymerisation stage produces at least 5% wt of the multimodal polyethylene, and the multimodal polyethylene has a multimodal molecular weight distribution, a molecular weight of at least 50,000 g/mol and a bulk density of at least 250 g/dm.sup.3, and wherein a solution of the unsupported metallocene catalyst in a solvent is employed. The present invention also provides a multimodal polyethylene, a process for preparing a pipe comprising preparing a multimodal polyethylene and extruding the multimodal recycle polyethylene to produce a pipe, and a pipe obtained by such a process.