Abstract: Methods and compositions for making organic crosslinkers having hindered urea bonds and methods and compositions for making dynamic crosslinked polymer networks using the organic crosslinkers via addition chemistry are provided. Also provided are methods for processing and reprocessing the dynamic crosslinked polymer networks in which the crosslinkers dissociate at elevated temperatures and recombine upon cooling. Polymer networks formed using the dynamic crosslinkers can be reprocessed multiple times at modest temperatures with full recovery of crosslink density.

Abstract: A composition for forming a dynamic crosslinked polymer network may comprise (a) a dynamic crosslinker having formula R—R?R?N—S—S—NR?R?—R, wherein each R is a polymerizable group comprising a carbon-carbon (C—C) double bond capable of undergoing free radical polymerization and each R? and each R? are independently selected alkyl groups; (b) a polymer comprising a C—C double bond capable of undergoing free radical polymerization, a monomer comprising a C—C double bond capable of undergoing free radical polymerization, or combinations thereof; and (c) a free radical initiator, wherein the dynamic crosslinker does not comprise a urethane group.

Abstract: A composition for forming a dynamic crosslinked polymer network may comprise (a) a dynamic crosslinker having formula R—R?R?N—S—S—NR?R?—R, wherein each R is a polymerizable group comprising a carbon-carbon (C—C) double bond capable of undergoing free radical polymerization and each R? and each R? are independently selected alkyl groups; (b) a polymer comprising a C?C double bond capable of undergoing free radical polymerization, a monomer comprising a C?C double bond capable of undergoing free radical polymerization, or combinations thereof; and (c) a free radical initiator, wherein the dynamic crosslinker does not comprise a urethane group.

Abstract: The present invention concerns a polyethylene composition comprising a blend of between 5 and 40 wt/% of first polyethylene produced with a chromium based catalyst and having an MFR2 between 0.01 and 1 g/10 min, wherein the first polyethylene is a high density polyethylene with a density between 940 and 965 kg/m3, and between 60 and 95 wt % of a second polyethylene with an MFR2 between >1 and 12 g/10 min. Such a blend may thereby be advantageously used especially for example in cable and wire applications.

Abstract: The present invention concerns a polyethylene composition comprising a blend of between 5 and 40 wt/% of first polyethylene produced with a chromium based catalyst and having an MFR2 between 0.01 and 1 g/10 min, wherein the first polyethylene is a high density polyethylene with a density between 940 and 965 kg/m3, and between 60 and 95 wt % of a second polyethylene with an MFR2 between >1 and 12 g/10 min. Such a blend may thereby be advantageously used especially for example in cable and wire applications.