The present disclosure describes, in part, an enzyme-mediated radical initiating system and methods of using the system to produce polymers, including polymeric hydrogels, at ambient conditions.

This invention relates bisindenyl metallocene catalyst compounds having long (at least 4 carbon atoms) linear alkyl groups substituted at the two position and substituted or unsubstituted aryl groups at the four position and process using such catalyst compounds, particularly in the solution process at higher temperatures.

This invention relates bisindenyl metallocene catalyst compounds having long (at least 4 carbon atoms) linear alkyl groups substituted at the two position and substituted or unsubstituted aryl groups at the four position and process using such catalyst compounds, particularly in the solution process at higher temperatures.

The present invention relates to a process for the preparation of a polyethylene wax, the process comprising the steps of providing a catalyst solution, wherein the catalyst solution comprises at least one activating compound, an alkylaluminoxane and a me-tallocene complex, wherein the molar ratio of the activating compound to aluminum comprised in the alkylaluminoxane is from 0.0005 to 0.20; and polymerizing ethylene, by contacting the ethylene and the catalyst solution.

The present invention relates to a process for the preparation of a polyethylene wax, the process comprising the steps of providing a catalyst solution, wherein the catalyst solution comprises at least one activating compound, an alkylaluminoxane and a me-tallocene complex, wherein the molar ratio of the activating compound to aluminum comprised in the alkylaluminoxane is from 0.0005 to 0.20; and polymerizing ethylene, by contacting the ethylene and the catalyst solution.

The present invention concerns type II photoinitiators for the free-radical crosslinking of silicone compositions, in particular acrylic silicone compositions. The present invention concerns a silicone composition C1 that can be crosslinked by exposure to radiation with a wavelength of between 300 and 450 nm, comprising: —at least one organopolysiloxane A comprising at least one methacrylate group bonded to a silicon atom, at least one organohydrogenopolysiloxane H comprising at least two, and preferably at least three hydrogen atoms each bonded to different silicon atoms, and—at least one free-radical photoinitiator P. The present invention also concerns the provision of a silicone composition that can be polymerized or crosslinked by free-radical process comprising a type II photoinitiator system suitable for crosslinking silicone compositions, in particular by exposure to radiation, and absorbing light radiation with a wavelength greater than 300 nm.

The present invention concerns type II photoinitiators for the free-radical crosslinking of silicone compositions, in particular acrylic silicone compositions. The present invention concerns a silicone composition C1 that can be crosslinked by exposure to radiation with a wavelength of between 300 and 450 nm, comprising:—at least one organopolysiloxane A comprising at least one methacrylate group bonded to a silicon atom, at least one organohydrogenopolysiloxane H comprising at least two, and preferably at least three hydrogen atoms each bonded to different silicon atoms, and—at least one free-radical photoinitiator P. The present invention also concerns the provision of a silicone composition that can be polymerized or crosslinked by free-radical process comprising a type II photoinitiator system suitable for crosslinking silicone compositions, in particular by exposure to radiation, and absorbing light radiation with a wavelength greater than 300 nm.

The present invention provides a preparing method of a polymer which is low-toxic, environmental-friendly, highly controllable, and low cost to obtain a polymer with high molecular weight. The preparing method comprises conducting a controlled radical polymerization process of monomer (Y). In the controlled radical polymerization process, organic compound (A) which has the formula (I) and radical initiator (B) are existing in a mole ratio (B/A) ranged from 0.5 to 25,

##STR00001## wherein R.sup.1 is a hydrogen atom, alkyl group, aryl group, or hydroxyl group, the alkyl group can be alkyl having substituents or alkyl substituent, and the aryl group can be aryl having substituents or aryl substituent.

An improved method of characterizing the PSD of particles.

An improved method of characterizing the PSD of particles.