Abstract: Reactive antioxidant compounds, able to stabilize organic polymers, contain in their molecule a sterically hindered phenolic group and a hydrolysable silyl function. In stabilizing organic polymers, said reactive antioxidant compounds can be hydrolysed at the silyl function with the formation of silanol groups, which are made to interact in order to form complex resinous stabilizing structures. These latter are added in stabilizing quantities to the polymer to be stabilized. According to one particular embodiment, the hydrolysis at the silyl function and the formation of the resinous structure take place spontaneously within the polymer to be stabilized. According to a further embodiment, the reactive antioxidant compound is added to the polymer after being stably supported on a solid support by reaction with an inorganic solid having surface hydroxyl groups.

Abstract: Stabilized polyolefinic compositions comprise a polyolefin, such as polyethylene and polypropylene and a stabilizing amount of an organic compound comprising at least one 3,3,5,5-tetramethylmorpholine or one 2,3,3,5,5-pentamethylene morpholine: ##STR1## wherein R is hydrogen or the methyl group; bearing a substituent on the carbon atom in the position 2 and/or on the nitrogen atom in the position 4 of the ring.

Abstract: A process for preparing 2,2-dialkyl-4-methyl-5,5-dialkyl-3-formyl-.DELTA..sup.3 -pyrrolines by reacting the corresponding dialkyl substituted di-tert-propargylamines with water at a pH equal to or less than 3.0. Preferably, an inorganic mercury compound is used as a catalyst.

Abstract: Polyolefin polymers can successfully be stabilized against the detrimental effects of UV-radiations by compounding them with a stabilizer belonging to the class of compounds containing a pyrrolidine ring and which are sterically hindered in the 3-position and also substituted in such position by substituents having a high molecular weight. The esters of the 2,2,5,5-tetraalkyl-4-methyl-3-methylol pyrrolidine are exemplary compounds; the adipic and the stearic esters are preferred.

Abstract: For stabilizing polyolefin polymers such as polyethylene and polypropylene against the detrimental effects of exposure to UV-radiations and weathering agents, a stabilizing additive is disclosed which consist of a fatty acid ester of the N-(beta-hydroxyethyl)-2,2,3,4,5,5-hexamethylpyrrolidine. The lauric and palmitic acid esters are preferred.

Abstract: This invention relates to particular polyolefin compositions which contain, as stabilizers against UV-light radiations, open-chain amine compounds which are hindered in the alpha-position by alkyl radicals, said amine compounds corresponding to the following general formula: ##STR1## wherein R', R", R"', R.sup.IV, R.sup.V and R.sup.VI which can be equal or different, are radicals of aliphatic hydrocarbons with a number of C-atoms variable from 1 to 20, or can be hydrogen atoms, n is an integer variable from 2 to 12, and n' is an integer comprised between 1 and 15.