The invention relates to a two-part dual cure dental composition with improved stability toward discoloration and premature polymerization. The dental composition comprises a Base Part and a Catalyst Part, the Base Part comprising polymerizable component(s) without an acidic moiety, optionally polymerizable component(s) with an acidic moiety, filler(s), transition metal component(s), peroxide component(s), stabilizer component(s) comprising a free-radical moiety, the Catalyst Part comprising polymerizable component(s) without an acidic moiety, filler(s), ascorbic acid component, photo-initiator system, stabilizer component(s) comprising a phosphite or sulfite moiety. The dental composition is in particular useful as bulk fill dental composite, dental resin cement, core build-up dental material or self- and dual cure dental adhesive. The invention further relates to an initiator system and the use of a stabilizer comprising a free-radical moiety.

The invention relates to the preparation of a water-soluble anionic polymer, the weight-average molecular mass M.sub.W of which ranges from 1,000 to 10,000 g/mol and the polydispersity index I.sub.p of which is less than 3.5. The polymer according to the invention is obtained by a polymerization reaction in water of an unsaturated anionic monomer, in the presence of Cu.sup.I or of Cu.sup.II and of an aromatic compound comprising a functional group chosen from hydroxyl, primary amine, secondary amine and tertiary amine directly bonded to the aromatic ring. The invention also relates to an aqueous composition comprising the polymer according to the invention.

The invention relates to the preparation of a water-soluble anionic polymer, the weight-average molecular mass M.sub.W of which ranges from 1,000 to 10,000 g/mol and the polydispersity index I.sub.p of which is less than 3.5. The polymer according to the invention is obtained by a polymerization reaction in water of an unsaturated anionic monomer, in the presence of Cu.sup.I or of Cu.sup.II and of an aromatic compound comprising a functional group chosen from hydroxyl, primary amine, secondary amine and tertiary amine directly bonded to the aromatic ring. The invention also relates to an aqueous composition comprising the polymer according to the invention.

The present disclosure provides a method of preparing a vinyl chloride-based polymer, and the method provides excellent productivity while having reduced amount of a volatile organic compound generated so as to provide the vinyl chloride-based polymer suitable for an eco-friendly material, and improved foaming and viscosity properties of a plastisol including the prepared polymer, by adding a carbonate-based metal salt and a transition metal catalyst together, and controlling input time and amount of the transition metal catalyst.

The present disclosure provides a method of preparing a vinyl chloride-based polymer, and the method provides excellent productivity while having reduced amount of a volatile organic compound generated so as to provide the vinyl chloride-based polymer suitable for an eco-friendly material, and improved foaming and viscosity properties of a plastisol including the prepared polymer, by adding a carbonate-based metal salt and a transition metal catalyst together, and controlling input time and amount of the transition metal catalyst.

The present disclosure relates to a multi- or dual-headed composition having the formula (I) or (II). The present disclosure also relates to a process for preparing the multi- or dual-headed composition having the formula (I) or (II), the process including combining 1,2,4-trivinylcyclochexane, an organometallic compound, and a catalyst precursor. The present disclosure further relates to use of the composition having the formula (I) or (II) in olefin polymerization.

The present disclosure relates to a multi- or dual-headed composition having the formula (I) or (II). The present disclosure also relates to a process for preparing the multi- or dual-headed composition having the formula (I) or (II), the process including combining 1,2,4-trivinylcyclochexane, an organometallic compound, and a catalyst precursor. The present disclosure further relates to use of the composition having the formula (I) or (II) in olefin polymerization.

Systems and methods for Atom Transfer Radical Polymerization (ATRP) emulsion polymerization are provided. The ATRP emulsion polymerization comprises a suspending medium, a dispersed medium, a surfactant, a transition metal compound in a higher oxidation state, a ligand, and an ATRP initiator. The transition metal compound is capable of forming a catalyst complex in a presence of the ligand. The catalyst complex is soluble in the suspending medium and is capable of forming an ionic complex with the surfactant. The ionic complex is capable of moving between the suspending medium and the dispersed medium. A portion of the transition metal compound in the higher oxidation state within a portion of the catalyst complex is reduced by a physical and/or a chemical procedure thereby initiating a polymerization of one or more radically (co)polymerizable monomers by reaction with the initiator.

Systems and methods for Atom Transfer Radical Polymerization (ATRP) emulsion polymerization are provided. The ATRP emulsion polymerization comprises a suspending medium, a dispersed medium, a surfactant, a transition metal compound in a higher oxidation state, a ligand, and an ATRP initiator. The transition metal compound is capable of forming a catalyst complex in a presence of the ligand. The catalyst complex is soluble in the suspending medium and is capable of forming an ionic complex with the surfactant. The ionic complex is capable of moving between the suspending medium and the dispersed medium. A portion of the transition metal compound in the higher oxidation state within a portion of the catalyst complex is reduced by a physical and/or a chemical procedure thereby initiating a polymerization of one or more radically (co)polymerizable monomers by reaction with the initiator.

Provided is a polymerization initiator, which has an excellent curing rate and is an alternative to a polymerization initiator system using a benzoyl peroxide-aromatic amine compound, a curable composition containing the polymerization initiator, a dental material and dental filler material containing the composition, and a kit for preparing the curable composition. The polymerization initiator contains one or more compounds (A) selected from the group consisting of a pyrazolidinedione compound and/or pyrazolidine(di)thione compound (A1), a salt (A2) of the compound (A1), and a malonate compound (A3).