摘要:
This invention includes a process for forming a thermoplastic vulcanizate comprising: (a) admixing a C-H insertion curing agent with at least one elastomeric phase polymer to form a first admixture; (b) admixing at least one non-elastomeric polyolefin with the first admixture to form a second admixture; and (c) heating the second admixture to a temperature at least the decomposition temperature of the curing agent to crosslink the elastomeric phase while mixing the admixture to an extent sufficient to result in the formation of a thermoplastic material, hereinafter referred to as a thermoplastic vulcanizate, and optionally including an additional step (d) of shaping the resulting thermoplastic vulcanizate, especially by heating and foaming or molding the TPV. The C-H insertion curing agent is preferably selected from alkyl and aryl azides (R-N3), acyl azides (R-C(O)N3), azidoformates ((R-O-C(O)-N3), sulfonyl azides (R-SO2-N3), phosphoryl azides (RO)2-(PO)-N3), phosphinic azides (R2-P(O)-N3) and silyl azides (R3-Si-N3), with poly(sulfonyl azide) most preferred. Additionally, the invention includes a thermoplastic vulcanizate comprising a blend of: (1) an elastomeric phase crosslinked using a C-H insertion curing agent dispersed in; (2) at least one non-elastomeric thermoplastic polyolefin. The invention also includes a foamable composition comprising (1) an elastomeric phase crosslinked using a C-H insertion curing agent dispersed in; (2) at least one non-elastomeric thermoplastic polyolefin; and (3) from 0.1 to 25 percent by weight based on the combined weight of components (1) and (2) of at least one foaming agent as well as a fabricated part, cable jacket, cable insulation, or foam comprising the thermoplastic vulcanizate or the invention or resulting from the process of the invention.
摘要:
A reversible, heat-set covered fiber is described, the covered fiber comprising: A. A core comprising an elastic fiber comprising a substantially crosslinked, temperature-stable, olefin polymer, and B. A cover comprising an inelastic fiber. The fiber is heat-set by a method comprising: (a) Stretching the covered fiber by applying a stretching force to the covered fiber; (b) Heating the stretched covered fiber of (a) to a temperature in excess of the crystalline melting point of the olefin polymer for a period of time sufficient to at least partially melt the olefin polymer; (c) Cooling the stretched and heated covered fiber of (b) to a temperature below the crystalline melting point of the olefin polymer for a period of time sufficient to solidify the polymer; and (d) Removing the stretching force from the covered fiber.
摘要:
Fibers having improved resistance to moisture at elevated temperatures comprise at least two elastic polymers, one polymer heat-settable and the other polymer heat-resistant, the heat-resistant polymer comprising at least a portion of the exterior surface of the fiber. The fibers typically have a bicomponent and/or a biconstituent core/sheath morphology. Typically, the core comprises an elastic thermoplastic urethane, and the sheath comprises a homogeneously branched polyolefin, preferably a homogeneously branched substantially linear ethylene polymer.
摘要:
Polyolefin compositions that expand freely to form stable foams are disclosed. The compositions include at least one heat-activated expanding agent and typically include at least one heat-expanded crosslinker. The compositions are effective as sealers and noise/vibration insulation in automotive applications.
摘要:
A polymeric composition having improved melt extrusion properties comprising: A) an olefin polymer; B) a catalyst neutralizer comprising a cationic derivative of a poly(oxyalkylene) compound; and C)a processing aid comprising an interactive diorganopolysiloxane compound containing hydroxyl-, carboxylic acid-, di(C1-20 hydrocarbyl)amino-, or C2-10 alkenyl-functional groups.
摘要:
Silane functional polymers having uniform silane distribution, long chain branching or tertiary silane functionality and conversion thereof through coupling, hydrolysis, hydrolysis and neutralization, condensation, oxidation or hydrosilation are disclosed.
摘要:
An olefin polymer composition comprises a stabilizing amount of a metal deactivator comprising a polymeric hydrazine derivative. The deactivator is of formula (I), in which at least one of R 1 and R 2 comprise a polymeric radical that includes a substituted or unsubstituted aromatic radical. The olefin polymers include polyethylene and polypropylene.
摘要:
The present invention relates to heat resistance elastic articles comprising a cured, irradiated, or crosslinked or ethylene polymer and a method for making the same. In particular, the invention relates to a shaped article (for example, film or fiber) characterized by improved elasticity at elevated temperatures and comprising a substantially cured, irradiated, or crosslinked homogeneously branched ethylene polymer. The improved elastic article of the present invention is particularly suitable for use in applications where good elasticity must be maintained at elevated temperatures such as, for example, personal hygiene items and disposable infection-control garments at body temperatures of about 100 °F (38 °C).
摘要:
A reversible, heat-set covered fiber is described, the covered fiber comprising: A. A core comprising an elastic fiber comprising a substantially crosslinked, temperature-stable, olefin polymer, and B. A cover comprising an inelastic fiber. The fiber is heat-set by a method comprising: (a) Stretching the covered fiber by applying a stretching force to the covered fiber; (b) Heating the stretched covered fiber of (a) to a temperature in excess of the crystalline melting point of the olefin polymer for a period of time sufficient to at least partially melt the olefin polymer; (c) Cooling the stretched and heated covered fiber of (b) to a temperature below the crystalline melting point of the olefin polymer for a period of time sufficient to solidify the polymer; and (d) Removing the stretching force from the covered fiber.
摘要:
Fibers having improved resistance to moisture at elevated temperatures comprise at least two elastic polymers, one polymer heat-settable and the other polymer heat-resistant, the heat-resistant polymer comprising at least a portion of the exterior surface of the fiber. The fibers typically have a bicomponent and/or a biconstituent core/sheath morphology. Typically, the core comprises an elastic thermoplastic urethane, and the sheath comprises a homogeneously branched polyolefin, preferably a homogeneously branched substantially linear ethylene polymer.