Abstract: Composite particles having a core consisting of an organic polymer and a coating including at least one aluminum, silicon, zirconium and/or transition metal oxide and/or hydroxide, and optionally containing calcium carbonate, as well as methods for preparing same, are disclosed. The use of said composite particles for preparing hollow particles with a shell of the same kind as the above-mentioned coating is also disclosed. Finally, the use of said hollow composite particles as fillers or additives in plastics and elastomers is disclosed.

Abstract: Composite core/sheath particulates comprising an organic polymer core at least partly coated with calcium carbonate, these core/sheath particulates having a mean particle size not exceeding 5 .mu.m, well suited for reinforcing plastic/elastomer substrates, are conveniently converted, e.g., via calcination, into hollow calcium carbonate microbeads which comprise CaCO.sub.3 shells having a mean particle size not exceeding 5 .mu.m; such hollow microbeads are themselves well suited for enhancing the low-temperature flexibility of elastomer substrates, notably vehicle tires.

Abstract: The present invention is directed to compositions containing novel beta-diketones of formula (I) and formula (II),R.sub.1 COCH.sub.2 COR.sub.2 (I)R.sub.2 COCH.sub.2 COR.sub.2 (II)which may be used to stabilize various polymers, such as polyvinyl chlorides (PVCs). The present invention is also directed to a method for preparing .beta.-diketones by a Claisen condensation reaction, which is represented as follows:R.sub.4 COCHR.sub.5 H+R.sub.6 C(O)OR.sub.7 +RO.sup.- .fwdarw.?R.sub.4 COCR.sub.5 COR.sub.6 !-+R.sub.7 OH+ROH.

Abstract: Composite core/sheath particulates comprising an organic polymer core at least partly coated with calcium carbonate, these core/sheath particulates having a mean particle size not exceeding 5 .mu.m, well suited for reinforcing plastic/elastomer substrates, are conveniently converted, e.g., via calcination, into hollow calcium carbonate microbeads which comprise CaCO.sub.3 shells having a mean particle size not exceeding 5 .mu.m; such hollow microbeads are themselves well suited for enhancing the low-temperature flexibility of elastomer substrates, notably vehicle tires.

Abstract: The invention relates to compositions for chlorine-containing polymer such as PVC, including a stabilizing composition.According to the invention the stabilizing composition includes:a) the unpurified crude product resulting from the reaction of condensation of an ester with a ketone in the presence of an alkaline agent, this crude product including between 10 and 95%, preferably between 20 and 80% by weight of beta-diketone, andb) a metal acetylacetonate complex,the ratio of the constituents a/b being between 50/50 and 1/99.The invention also relates to the standard objects obtained from these compositions.

Abstract: The present invention relates to a stabilizing composition for a chlorine-containing polymer (PVC), characterized in that it comprises the unpurified crude product resulting from the reaction of an ester with a ketone in the presence of an alkaline agent, this crude product comprising at least 10 % by weight of .beta.-diketone and being in the form of a powder.

Abstract: The present invention is directed to compositions containing novel beta-diketones of formula (I) and formula (II),R.sub.1 COCH.sub.2 COR.sub.2 (I)R.sub.2 COCH.sub.2 COR.sub.2 (II)which may be used to stabilize various polymers, such as polyvinyl chlorides (PVCs). The present invention is also directed to a method for preparing .beta.-diketones by a Claisen condensation reaction, which is represented as follows:R.sub.4 COCHR.sub.5 H+R.sub.6 C(O)OR.sub.7 +RO.sup.- .fwdarw.[R.sub.4 COCR.sub.5 COR.sub.6 ]--+R.sub.7 OH+ROH.

Abstract: Novel dihydropyridine compounds bearing substituted piperidyl substituents are effective heat/light stabilizers for a wide variety of polymer substrates, e.g., for halopolymers such as PVC, and are also effective anti-UV agents and antioxidants for such polymers as polyolefins, polystyrenes, polyalkadienes, polyurethanes, polyamides, polyesters, polycarbonates, polysulfones, polyethersulfones, polyetherketones, acrylic polymers, or copolymers or mixtures thereof.