摘要:
The co-polymerization reaction of one or more olefin monomers, such as propylene, with &agr;,&ohgr;-diene units and the resulting copolymers are provided. More specifically, the copolymer may have from 90 to 99.999 weight percent of olefins and from 0.001 to 2.000 weight percent of &agr;,&ohgr;-dienes. The copolymer may have a weight average molecular weight in the range from 50,000 to 2,000,000, a crystallization temperature in the range from 115° C. to 135° C. and a melt flow rate in the range from 0.1 dg/min to 100 dg/min. These copolymers may be employed in a wide variety of applications, the articles of which include, for example, films, fibers, such as spunbonded and meltblown fibers, fabrics, such as nonwoven fabrics, and molded articles. The copolymer may further include at least two crystalline populations. Desirably, the melting point range of one of the crystalline populations is distinguishable from the melting point range of another crystalline population by a temperature range of from 1° C. to 8° C. More desirably, one of the crystalline populations has a melting point in the range from 152° C. to 158° C. and another crystalline population has a melting point in the range from 142° C. to 148° C.
摘要:
This invention relates to compositions derived from polyolefins combined with a polymeric nucleating agent. The nucleating agent is specifically a diene-propylene copolymer.
摘要:
Electrically conductive compositions comprising an ethylene polymer, a mineral filler and carbon black having a surface area greater than about 500 m.sup.2 /gram, these compositions being useful as extrudates about electrical conductors providing conductive shields thereon.
摘要:
Isotactic polypropylene ethylene-propylene copolymer blends and in-line processes for producing. The blends may have between 1 and 50 wt % of isotactic polypropylene with a melt flow rate of between 0.5 and 20,000 g/10 min and a melting peak temperature of 145° C. or higher, and wherein the difference between the DSC peak melting and the peak crystallization temperatures is less than or equal to 0.5333 times the melting peak temperature minus 41.333° C., and between 50 and 99 wt % of ethylene-propylene copolymer including between 10 wt % and 20 wt % randomly distributed ethylene with a melt flow rate of between 0.5 and 20,000 g/10 min, wherein the copolymer is polymerized by a bulk homogeneous polymerization process, and wherein the total regio defects in the continuous propylene segments of the copolymer is between 40 and 150% greater than a copolymer of equivalent melt flow rate and wt % ethylene polymerized by a solution polymerization process.
摘要:
An adhesive and method for hot melt application. The adhesive comprises polyolefin base polymer, from 1 to 10 wt % of at least one functionalized polyolefin, and from 1 to 15 wt % of a wax, based on the total weight of the polyolefin base polymer, functionalized polyolefin and wax, wherein the wax has a weight average molecular weight at least 8% of the weight average molecular weight of the polyolefin base polymer, viscosity at 190° C. of 60 mPa·s or more, and a crystallization temperature greater than the polyolefin base polymer and greater than 100° C., and wherein the adhesive has at least 5% fiber tear at 2° C., at least 50% fiber tear at 25° C., and a characteristic set time of less than 3 seconds.
摘要:
The present invention relates to a process for preparing a thermoplastic vulcanizate (TPV) comprising: contacting a thermoplastic polymer, a cross-linkable elastomer, at least one curative, and at least one cure activator in a solvent to form Composition A. The solvent is then removed, and thereafter the cross-linkable elastomer is at least partially cured. The average particle size of the cross-linkable elastomer is 10 microns or less after the solvent is removed.
摘要:
The present invention relates to a process for preparing a thermoplastic vulcanizate (TPV) comprising: contacting a thermoplastic polymer, a cross-linkable elastomer, at least one curative, and at least one cure activator in a solvent to form Composition A. The solvent is then removed, and thereafter the cross-linkable elastomer is at least partially cured. The average particle size of the cross-linkable elastomer is 10 microns or less after the solvent is removed.
摘要:
In a process for producing a heterogeneous polymer blend, at least one first monomer is polymerized in a first reaction zone in the presence of a supported catalyst to produce a thermoplastic first polymer having a crystallinity of at least 30%. At least part of said first polymer is then contacted with at least one second monomer and at least one polyene in a second reaction zone under conditions sufficient to polymerize said second monomer to produce a second polymer having a crystallinity of less than 20%. The second polymer is at least partially cross-linked in the second reaction zone such that at least a fraction of the second polymer is insoluble in xylene and such that the first and second polymers form different phases of the blend.
摘要:
Isotactic polypropylene ethylene-propylene copolymer blends and in-line processes for producing them. The blend of polypropylene and ethylene-propylene copolymer may have between 1 and 50 wt % of isotactic polypropylene with a melt flow rate of between 0.5 and 20,000 g/10 min and a melting peak temperature of 145° C. or higher, and wherein the difference between the DSC peak melting and the peak crystallization temperatures is less than or equal to 0.5333 times the melting peak temperature minus 41.333° C., and between 50 and 99 wt % of ethylene-propylene copolymer including between 10 wt % and 20 wt % randomly distributed ethylene with a melt flow rate of between 0.5 and 20,000 g/10 min, wherein the copolymer is polymerized by a bulk homogeneous polymerization process, and wherein the total regio defects in the continuous propylene segments of the copolymer is between 40 and 150% greater than a copolymer of equivalent melt flow rate and wt % ethylene polymerized by a solution polymerization process. The in-line process for producing the blend includes providing two or more parallel reactor trains and a separator for product blending and product-feed separation; wherein the two or more reactor trains operate under fluid phase bulk homogeneous conditions and at least one of the trains operates under supercritical conditions.
摘要:
This invention relates to a molded article comprising a heterogeneous blend that includes: 1) from 60 to 99 weight percent of one or more semi-crystalline propylene homopolymers or copolymers having a melting point between 100 and 170 ° C. and a melt flow rate of 200 dg/min or less; and 2) from 1 to 40 weight % of one or more semi-amorphous propylene /C2 and/or C4 to C10 α-olefin copolymers each having a particular heat of fusion, a melt flow rate, intermolecular compositional distribution as determined by thermal fractionation in hexane, Mw/Mn, and propylene triad tacticity such that the molded part formed from the resulting blend has improved notched impact strength, flexibility, elongation, and resistance to stress whitening at a thickness of from 250 μpm to 10 mm.