Process for the preparation of substantially amorphous alpha-olefin polymers and compositions containing them and process for the preparation of bridged ligand
AssigneeBasell Polyolefine GmbH
InventorsLuigi Resconi, Davide Balboni
Life of this patent
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Abstract
Amorphous polymers of alpha-olefins, particularly of propylene, having high molecular weights and narrow molecular weight distributions, in which the isotactic sequences are more abundant than the syndiotactic ones, can be obtained in high yields at temperatures of industrial interest by carrying out the polymerization reaction in the presence of metallocene catalysts comprising particular bridged bis-indenyl compounds substituted in the 3-position on the indenyl groups. The obtained amorphous polymers are particularly useful for the preparation of miscible compositions with substantially isotactic alpha-olefins.
Claims39
A process for the preparation of amorphous polymers of alpha-olefins, comprising the polymerization reaction of at least one alpha-olefin containing from 3 to 20 carbon atoms in the presence of a catalyst obtainable by contacting:
- (A) a metallocene compound in the racemic form of the formula (I)
- 8
- wherein
- substituents R1 are hydrogen atoms;
- R2 and R3 are, independently from each other, C1-C20-alkyl, C3-C20-cycloalkyl, C2-C20-alkenyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radicals, optionally containing silicon or germanium atoms;
- or where R2 and R3 can be joined together to form a 4 to 6 membered ring or a 6 to 20 fused ring system;
- R4 and R5, same or different, are hydrogen atoms or —CHR8R9 groups;
- R4 and R5 can form a ring having 3 to 8 carbon atoms which can contain hetero atoms;
- the R8 and R9 substituents, same or different, are hydrogen atoms, C1-C20-alkyl, C3-C20-cycloalkyl, C2-C20-alkenyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radicals, which can form a ring having 3 to 8 carbon atoms which can contain hetero atoms;
- the R6 and R7 substituents, same or different, are hydrogen, C1-C20-alkyl, C3-C20-cycloalkyl, C2-C20-alkenyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radicals, optionally containing silicon or germanium atoms;
- and optionally two adjacent R6 and R7 substituents can form a ring comprising from 5 to 8 carbon atoms;
- M is a transition metal selected from those belonging to group 3, 4, 5, 6 or to the lanthanide or actinide groups in the Periodic Table of the Elements (new IUPAC version),
- X, same or different, is a monoanionic ligand, such as a hydrogen atom, a halogen atom, an R10, OR10, OSO2CF3, OCOR10, SR10, NR102 or PR102, group, wherein the substituents R10 are a C1-C20-alkyl, C3-C20-cycloalkyl, C2-C20-alkenyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radical, optionally containing silicon or germanium atoms;
- p is an integer from 0 to 3, p being equal to the oxidation state of the metal M minus two;
- and
- (B) an alumoxane and/or a compound capable of forming an alkyl metallocene cation.
A thermoplastic composition comprising:
- (A) 1 to 99% by weight of a propylene polymer optionally containing from 0.1 to 20% by moles of units deriving from an olefin of formula CH2═CHR, R being hydrogen, a C2-C20-alkyl or a C6-C12-aryl group, having the following characteristics:
- melting enthalpy <70 J/g;the ratio of the pentads (mmmm)/(rrrr)=1,5;
- andthe ratio of the pentads (mmmm)/(mmmr)=0.8;
- (B) 1 to 99% by weight of a propylene polymer, optionally containing from 0.1 to 20% by moles of units deriving from an olefin of formula CH2═CHR, R being hydrogen, a C2-C20-alkyl or a C6-C13-aryl group, having the following characteristics:
- melting enthalpy>70 J/g, and% of isotactic dyads (m)−% of syndiotactic dyads (r)>0.
Dependencies are inferred from the claim text.