The present invention relates to the use of at least one phenolically substituted sugar derivative as a stabiliser of organic materials, in particular plastics, against oxidative, thermal and/or actinic degradation. The present invention also relates to a corresponding plastic composition, to a method for stabilising plastics, to a moulding compound or a moulded part as well as a phenolically substituted sugar derivative.

The present invention relates to the use of at least one phenolically substituted sugar derivative as a stabiliser of organic materials, in particular plastics, against oxidative, thermal and/or actinic degradation. The present invention also relates to a corresponding plastic composition, to a method for stabilising plastics, to a moulding compound or a moulded part as well as a phenolically substituted sugar derivative.

A process for enhancing the melt strength of polypropylene by extruding said polypropylene in a twin-screw extruder, under inert atmosphere, at a temperature between about 150° C. and about 300° C., and in the presence of about 0.1 to about 3.0 wt %, based on the weight of the polypropylene, of a para-substituted dibenzoyl peroxide.

A process for enhancing the melt strength of polypropylene by extruding said polypropylene in a twin-screw extruder, under inert atmosphere, at a temperature between about 150° C. and about 300° C., and in the presence of about 0.1 to about 3.0 wt %, based on the weight of the polypropylene, of a para-substituted dibenzoyl peroxide.

A methacrylic resin composition comprises a methacrylic resin, the methacrylic resin comprising: 50 mass % to 97 mass % of a methacrylic acid ester monomer unit (A); 3 mass % to 30 mass % of a structural unit (B) having a cyclic structure-containing main chain; and 0 mass % to 20 mass % of another vinyl monomer unit (C) that is copolymerizable with a methacrylic acid ester monomer, wherein the methacrylic resin satisfies a specific condition; and the composition has a weight average molecular weight residual ratio of 80% or more upon heating under a nitrogen atmosphere at 280° C. for 1 hour, and has a weight average molecular weight residual ratio of 80% or more upon heating in air at 280° C. for 0.5 hours.

A methacrylic resin composition comprises a methacrylic resin, the methacrylic resin comprising: 50 mass % to 97 mass % of a methacrylic acid ester monomer unit (A); 3 mass % to 30 mass % of a structural unit (B) having a cyclic structure-containing main chain; and 0 mass % to 20 mass % of another vinyl monomer unit (C) that is copolymerizable with a methacrylic acid ester monomer, wherein the methacrylic resin satisfies a specific condition; and the composition has a weight average molecular weight residual ratio of 80% or more upon heating under a nitrogen atmosphere at 280° C. for 1 hour, and has a weight average molecular weight residual ratio of 80% or more upon heating in air at 280° C. for 0.5 hours.

Provided is a curable composition which has excellent thin-film curability and which can form, via the application of light and/or heat, a cured product having heat resistance and thermal yellowing resistance at excellent levels. This curable composition contains cationically curable compounds and a cationic-polymerization initiator. The cationically curable compounds include an epoxy compound (A) in an amount of 10 to 90 weight percent of the total weight of the cationically curable compounds, and an oxetane compound (B) in an amount of 5 to 40 weight percent of the total weight of the cationically curable compounds. The cationic-polymerization initiator includes an onium borate salt (C). The onium borate salt (C) preferably has an anionic moiety selected from [(C.sub.6H.sub.5)B(C.sub.6F.sub.5).sub.3].sup.−, [(C.sub.6H.sub.5)B((CF.sub.3CF.sub.2).sub.2C.sub.6H.sub.2F).sub.3].sup.−, and [(C.sub.6H.sub.5C.sub.6H.sub.4)B(C.sub.6F.sub.5).sub.3].sup.− and a cationic moiety selected from arylsulfonium ions.

Provided is a curable composition which has excellent thin-film curability and which can form, via the application of light and/or heat, a cured product having heat resistance and thermal yellowing resistance at excellent levels. This curable composition contains cationically curable compounds and a cationic-polymerization initiator. The cationically curable compounds include an epoxy compound (A) in an amount of 10 to 90 weight percent of the total weight of the cationically curable compounds, and an oxetane compound (B) in an amount of 5 to 40 weight percent of the total weight of the cationically curable compounds. The cationic-polymerization initiator includes an onium borate salt (C). The onium borate salt (C) preferably has an anionic moiety selected from [(C.sub.6H.sub.5)B(C.sub.6F.sub.5).sub.3].sup.−, [(C.sub.6H.sub.5)B((CF.sub.3CF.sub.2).sub.2C.sub.6H.sub.2F).sub.3].sup.−, and [(C.sub.6H.sub.5C.sub.6H.sub.4)B(C.sub.6F.sub.5).sub.3].sup.− and a cationic moiety selected from arylsulfonium ions.

The present invention discloses a 3-aryl-benzofuranone compound in which R.sub.1-R.sub.6, in the formula are mutually independent H or C.sub.1-C.sub.20 alkyls, and R.sub.7 is C.sub.7-C.sub.20 alkyl or C.sub.7-C.sub.20 mixed alkyl. The present invention also discloses a composition of 3-aryl-benzofuranone compound and the preparation method. The 3-aryl-benzofuranone compound and the composition thereof has the superiority in application due to the characteristics of less proneness to volatilize, less proneness to be extracted, higher resistance to migration and less proneness to bloom and precipitate on the surface of organic materials, and with a wide range of application, it is effective during the application.

Provided are: a thermal stabilizer composition which does not generate an odor of a phosphorus-based antioxidant; and a synthetic resin composition comprising the same. The thermal stabilizer composition comprises: 100 parts by mass of a phosphorus-based antioxidant having a phosphite structure; and 0.001 to 10 parts by mass of a phenolic antioxidant having a substructure represented by the following Formula (1):

##STR00001## (wherein, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms; a represents an integer of 0 to 2; and, when a is 2, plural R.sup.3s are optionally the same or different).