摘要:
Methods for producing a silyl-functionalized polyolefin with silyl monomer incorporation are provided. The method includes reacting a silicon-containing olefin with an α-olefin, in the presence of a catalytic amount of a group IV catalyst for a time sufficient to produce a silyl-functionalized polyolefin.
摘要:
Methods for producing a silyl-functionalized polyolefin with silyl monomer incorporation are provided. The method includes reacting a silicon-containing olefin with an α-olefin, in the presence of a catalytic amount of a group IV catalyst for a time sufficient to produce a silyl-functionalized polyolefin.
摘要:
The invention provides a process for grafting silane or silicone functionality onto a polyolefin, comprising reacting the polyolefin with an unsaturated monomer (A) containing an olefinic —C═C— bond or acetylenic —C≡C— bond and a reactive functional group X in the presence of means capable of generating free radical sites in the polyolefin and with an organosilicon compound (B) having a functional group Y which is reactive with the functional group X of the unsaturated monomer (A), characterized in that the unsaturated monomer (A) contains an aromatic ring or a further olefinic double bond or acetylenic unsaturation, the aromatic ring or the further olefinic double bond or acetylenic unsaturation being conjugated with the olefinic —C═C— or acetylenic —C≡C— unsaturation of the unsaturated monomer (A).
摘要:
The invention provides a process for grafting silicone onto a polyolefin comprising reacting the polyolefin with a silicon compound containing an unsaturated group in the presence of means capable of generating free radical sites in the polyolefin, characterized in that the silicon compound is a branched silicone resin containing at least one group of the formula —X—CH═CH—R″ (I) or —X—C≡C—R″ (II), in which X represents a divalent organic linkage having an electron withdrawing effect with respect to the —CH═CH— or —C≡C-bond and/or containing an aromatic ring or a further olefinic double bond or acetylenic unsaturation, the aromatic ring or the further olefinic double bond or acetylenic unsaturation being conjugated with the olefinic unsaturation of —X—CH═CH—R″ or with the acetylenic unsaturation of —X—C≡C—R″, X being bonded to the branched silicone resin by a C—Si bond, and R″ represents hydrogen or a group having an electron withdrawing effect or any other activation effect with respect to the —CH═CH— or —C□C-bond. The polyolefin is reinforced by grafting the branched silicone resin onto it.
摘要:
The invention provides a composition comprising a polyolefin and a polyorganosiloxane in which at least 50 mole % of the siloxane units are D units as herein defined and which contains at least one unsaturated group, characterized in that the unsaturated group is group of the formula —X—CH═CH—R″ (I) or —X—C≡C—R″ (II), in which X represents a divalent organic linkage having an electron withdrawing effect with respect to the —CH═CH— or —C≡C— bond and/or containing an aromatic ring or a further olefinic double bond or acetylenic unsaturation, the aromatic ring or the further olefinic double bond or acetylenic unsaturation being conjugated with the olefinic unsaturation of —X—CH═CH—R″ or with the acetylenic unsaturation of —X—C≡C—R″ and R″ represents hydrogen or a group having an electron withdrawing effect or any other activation effect with respect to the —CH═CH— or —C≡C— bond.
摘要:
The invention relates to a process for grafting hydrolysable silane groups to a polyolefin in which ethylene units, if present, form less than 50% by weight of the total polyolefin. The polyolefin is reacted with an unsaturated silane, having at least one hydrolysable group bonded to Si, or a hydrolysate thereof, in the presence of means capable of generating free radical sites in the polyolefin. The unsaturated silane has the formula R″—CH═CH—Z (I) or R″—C≡C—Z (II) in which Z represents an electron-withdrawing moiety substituted by a —SiRaR′(3-a) group wherein R represents a hydrolysable group; R′ represents a hydrocarbyl group having 1 to 6 carbon atoms; a has a value in the range 1 to 3 inclusive; and R″ represents hydrogen or a group having an electron withdrawing or any other activation effect with respect to the —CH═CH— or —C≡C— bond. The use of an unsaturated silane of the formula R″—CH═CH—Z (I) or R″—C≡C—Z (II) in carrying out the grafting reaction on the polyolefin may give enhanced grafting yield compared to grafting with an olefinically unsaturated silane such as vinyltrimethoxysilane not containing an electron withdrawing moiety Z. The invention permits to provide a silane-modified polyolefin having a high grafting efficiency while limiting/preventing polymer degradation by chain scission. The silane-modified polyolefin can be further reacted with a polar surface, a filler or a polar polymer or reacted on itself to crosslink the polyolefin and obtain enhanced physical properties of the composites made thereof.
摘要:
The invention provides a composition comprising a polyolefin and a polyorganosiloxane in which at least 50 mole % of the siloxane units are D units as herein defined and which contains at least one unsaturated group, characterized in that the unsaturated group is group of the formula —X—CH═CH—R″ (I) or —X—C≡C—R″ (II), in which X represents a divalent organic linkage having an electron withdrawing effect with respect to the —CH═CH— or —C≡C— bond and/or containing an aromatic ring or a further olefinic double bond or acetylenic unsaturation, the aromatic ring or the further olefinic double bond or acetylenic unsaturation being conjugated with the olefinic unsaturation of —X—CH═CH—R″ or with the acetylenic unsaturation of —X—C≡C—R″ and R″ represents hydrogen or a group having an electron withdrawing effect or any other activation effect with respect to the —CH═CH— or —C≡C— bond.
摘要:
This invention relates to the modification of elastomers by reaction with unsaturated silanes, to the modified elastomers produced and to articles produced by shaping and curing modified elastomer compositions. It also relates to the use of unsaturated silanes as coupling agents in filled elastomer compositions. In a process according to the present invention, the silane has the formula: R″—CH═CH—C(O)X—Y—SiRaR′(3-a) (I) or R″—C≡C—C(O)X—Y—SiRaR′(3-a) (II) in which R represents a hydrolysable group; R′ represents a hydrocarbyl group having 1 to 6 carbon atoms; a has a value in the range 1 to 3 inclusive; Y represents a divalent organic spacer linkage comprising at least one carbon atom separating the linkage —C(O)X— from the Si atom, X is selected from S or O; and R″ represents hydrogen or a group having an electron withdrawing effect with respect to the —CH═CH— or —C≡C— bond. This provides silanes able to react efficiently with a diene elastomer in the presence of a free radical initiator.
摘要:
The invention provides a process for grafting silane or silicone functionality onto a polyolefin, comprising reacting the polyolefin with an unsaturated monomer (A) containing an olefinic —C═C— bond or acetylenic —C≡C— bond and a reactive functional group X in the presence of means capable of generating free radical sites in the polyolefin and with an organosilicon compound (B) having a functional group Y which is reactive with the functional group X of the unsaturated monomer (A), characterized in that the unsaturated monomer (A) contains an aromatic ring or a further olefinic double bond or acetylenic unsaturation, the aromatic ring or the further olefinic double bond or acetylenic unsaturation being conjugated with the olefinic —C═C— or acetylenic —C≡C— unsaturation of the unsaturated monomer (A).
摘要:
The invention relates to a process for grafting hydrolysable silane groups to a polyolefin in which ethylene units, if present, form less than 50% by weight of the total polyolefin. The polyolefin is reacted with an unsaturated silane, having at least one hydrolysable group bonded to Si, or a hydrolysate thereof, in the presence of means capable of generating free radical sites in the polyolefin. The unsaturated silane has the formula R″—CH═CH—Z (I) or R″—C≡C—Z (II) in which Z represents an electron-withdrawing moiety substituted by a —SiRaR′(3-a) group wherein R represents a hydrolysable group; R′ represents a hydrocarbyl group having 1 to 6 carbon atoms; a has a value in the range 1 to 3 inclusive; and R″ represents hydrogen or a group having an electron withdrawing or any other activation effect with respect to the —CH═CH— or —C≡C— bond. The use of an unsaturated silane of the formula R″—CH═CH—Z (I) or R″—C≡C—Z (II) in carrying out the grafting reaction on the polyolefin may give enhanced grafting yield compared to grafting with an olefinically unsaturated silane such as vinyltrimethoxysilane not containing an electron withdrawing moiety Z. The invention permits to provide a silane-modified polyolefin having a high grafting efficiency while limiting/preventing polymer degradation by chain scission. The silane-modified polyolefin can be further reacted with a polar surface, a filler or a polar polymer or reacted on itself to crosslink the polyolefin and obtain enhanced physical properties of the composites made thereof.