This invention is based upon the unexpected finding that the reaction product of polyisobutylene and a silane can be incorporated into tire sealant formulations to greatly reduce the level of hysteresis exhibited by such sealant formulations which decreases the rolling resistance of the tire to improve fuel economy. This is made possible by the further unexpected fining that silanes will react with polyisobutylene by a reaction which is initiated with a peroxide. This invention more specifically discloses a sealant composition which is particularly useful in manufacturing self-sealing tires and which is comprised of (a) the reaction product of polyisobutylene and a silane; and (b) a reinforcing filler. The sealant compositions also contain a peroxide to facilitate partial degradation of the polyisobutylene rubber during the curing of the tire.

This invention is based upon the unexpected finding that the reaction product of polyisobutylene and a silane can be incorporated into tire sealant formulations to greatly reduce the level of hysteresis exhibited by such sealant formulations which decreases the rolling resistance of the tire to improve fuel economy. This is made possible by the further unexpected fining that silanes will react with polyisobutylene by a reaction which is initiated with a peroxide. This invention more specifically discloses a sealant composition which is particularly useful in manufacturing self-sealing tires and which is comprised of (a) the reaction product of polyisobutylene and a silane; and (b) a reinforcing filler. The sealant compositions also contain a peroxide to facilitate partial degradation of the polyisobutylene rubber during the curing of the tire.

Crosslinked polymers and their uses in electrochemical systems, for example, as electrolyte membrane, are described. More precisely, these crosslinked polymers are formed by the crosslinking of a random copolymer based on monomers of glycidyl methacrylate or acrylate and of poly(ethylene glycol) methyl acrylate or methacrylate with a volatile polyamine crosslinking agent.

The present invention relates to a polyethylene homo- or copolymer having improved wear properties. In particular, the invention relates to an ultra-high molecular weight polyethylene having improved wear properties prepared using a heterogeneous Ziegler catalyst system. Said polyethylene homo- or copolymer is characterized in that the abrasion index of said polyethylene is related to the elongational stress according to the formula (I): in which ES=elongational stress as measured according to ISO 11542-2:1998 AI=abrasion index, as measured according to ISO 15527:2010 where the reference material according to ISO 15527:2010 is set to 100; β<1.8; and −0.015<a<−0.017.

[00001]$\begin{array}{cc}\mathrm{AI}<\frac{\mathrm{ES}-\beta }{\alpha }& \left(I\right)\end{array}$

The present invention relates to a polyethylene homo- or copolymer having improved wear properties. In particular, the invention relates to an ultra-high molecular weight polyethylene having improved wear properties prepared using a heterogeneous Ziegler catalyst system. Said polyethylene homo- or copolymer is characterized in that the abrasion index of said polyethylene is related to the elongational stress according to the formula (I): in which ES=elongational stress as measured according to ISO 11542-2:1998 AI=abrasion index, as measured according to ISO 15527:2010 where the reference material according to ISO 15527:2010 is set to 100; β<1.8; and −0.015<a<−0.017.

[00001]$\begin{array}{cc}\mathrm{AI}<\frac{\mathrm{ES}-\beta }{\alpha }& \left(I\right)\end{array}$

Novel catalytic compositions are disclosed comprising novel unsymmetrical metallocene catalytic compounds. Also disclosed are uses of such catalytic compositions in olefin polymerisation reactions, as well as processes of polymerising olefins. When compared with the prior art compositions, the catalytic compositions of the invention are markedly more active in the polymerisation of olefins.

Novel catalytic compositions are disclosed comprising novel unsymmetrical metallocene catalytic compounds. Also disclosed are uses of such catalytic compositions in olefin polymerisation reactions, as well as processes of polymerising olefins. When compared with the prior art compositions, the catalytic compositions of the invention are markedly more active in the polymerisation of olefins.

The Zigler-Natta catalyst composition of the present disclosure provides uniform polyethylene having a molecular weight in the range from 1 million g/mol to 12 million g/mol. The Zigler-Natta catalyst composition of the present disclosure comprises external electron donor selected from the group consisting of substituted silanediyl diacetate, trialkyl borate and tetraalkoxysilane.

The Zigler-Natta catalyst composition of the present disclosure provides uniform polyethylene having a molecular weight in the range from 1 million g/mol to 12 million g/mol. The Zigler-Natta catalyst composition of the present disclosure comprises external electron donor selected from the group consisting of substituted silanediyl diacetate, trialkyl borate and tetraalkoxysilane.

A polymer composition for producing gel extruded articles is described. The polymer composition contains polyethylene particles combined with a plasticizer. The polyethylene polymer has a narrow molecular weight distribution. Polymer articles made in accordance with the present disclosure have enhanced strength properties. In one embodiment, the polymer composition is used to form a porous membrane for use as a separator in electronic devices.