Propylene polymers and their preparation

Claim 2

A substantially amorphous random interpolymer comprising from l0 wt % to 30 wt % of units derived from ethylene, from 65 to 90 wt % of units derived from propylene and, optionally, up to l5 wt % of units derived from a C₄ - C₈ alpha-olefin, the interpolymer having a tacticity index m/r of from 3 to 5 as determined by ¹³C NMR spectra.

Claim 3

An interpolymer according to claim l comprising only units derived from ethylene and propylene having a tacticity index from 3 to 4.

Claim 4

An interpolymer according to claim l wherein the alpha-olefin is butene-l.

Claim 5

An interpolymer according to any one of claims l to 3 exhibiting a birefringent structure of spherulite granules by hot stage microscopy, the average length of the granules being from l5 to 50 micrometers.

Claim 6

An interpolymer according to any one of claims l to 3 exhibiting no significant crystallinity as determined by the presence of no more than 2 rings under wide angle x-ray diffraction.

Claim 7

An interpolymer according to any one of claims l to 5 having a heat of fusion of less than 0.6 cal/g.(2.5 J/g).

Claim 8

An interpolymer according to any one of claims l to 6 having a viscosity of from l000 to 25,000 cps (l to 25 Pas) at 375°F (l9l°C).

Claim 9

An interpolymer according to any of claims l to 7 having a ring and ball softening point of from 235°F (ll3°C) to 270°F (l32°C).

Claim 10

An interpolymer according to any one of claims l to 8 having a needle penetration in the range of from 25 to 75 dmm.

Claim 11

l0. An interpolymer according to any one of claims l to 9 having an open time of from l0 to 60 seconds.

Claim 12

A process for the production of a substantially amorphous interpolymer which comprises polymerizing from 65 to 90 wt % propylene, from l0 to 30 wt % ethylene and, optionally, up to l5 wt % of a C₄ - C₈ alpha-olefin at a temperature of from l30°F (54°C) to l75°F (79°C) and at a reactor pressure sufficient to maintain propylene in a liquid phase, in the presence of from 0.7 to 3.0 mol % hydrogen based on the monomer feed to the process, in the presence of a catalyst comprising: (a) a solid catalyst component produced by co-comminuting a magnesium halide support base and an aluminum trihalide in the absence of any added electron donor and co-comminuting the product obtained with a titanium tetrahalide in the absence of any added electron donor; and (b) a co-catalyst component comprising a mixture of from l5 to 90 mol % of a trialkylaluminum compound and from 85 to l0 mol % of an alkylaluminum halide having at least one halide per molecule, wherein each alkyl group of the trialkylaluminum and alkylaluminum halide, which alkyl groups may be identical or different, contains from l to 9 carbon atoms to provide an Al:Ti ratio in the co-catalyst component of from 50:l to 600:l the above mol %s being relative to the total amount of co-catalyst component,

Claim 13

A process for the production of a substantially amorphous interpolymer which comprises polymerizing from 65 to 90 wt % propylene, from l0 to 30 wt % ethylene and, optionally, up to l5 wt % of a C₄ - C₈ alpha-olefin at a temperature of from l30°F (54°C) to l75°F (79°C) and at a reactor pressure sufficient to maintain propylene in a liquid phase, in the presence of from 0.7 to 3.0 mol % hydrogen based on the monomer feed to the process, in the presence of a catalyst comprising: (a) a solid catalyst component produced by co-comminuting a magnesium halide support base and an aluminum trihalide in the absence of any added electron donor and co-comminuting the product obtained with a titanium tetrahalide in the absence of any added electron donor; and (b) a co-catalyst component comprising a mixture of from l5 to 90 mol % of a trialkylaluminum compound and from 85 to l0 mol % of an alkylaluminum halide having at least one halide per molecule, wherein each alkyl group of the trialkylaluminum and alkylaluminum halide, which alkyl groups may be identical or different, contains from l to 9 carbon atoms to provide an Al:Ti ratio in the co-catalyst component of from 50:l to 600:l the above mol %s being relative to the total amount of co-catalyst component,

Claim 14

and recovering a substantially amorphous, random interpolymer having a tacticity index m/r of from 3 to 5 as determined by ¹³C NMR spectra.

Claim 15

and recovering a substantially amorphous, random interpolymer having a tacticity index m/r of from 3 to 5 as determined by ¹³C NMR spectra.

Claim 16

A process according to claim ll wherein each halide is chloride, each alkyl is an ethyl group and the alkylaluminum halide is diethylaluminum chloride.

Claim 17

A process according to claim ll or l2 wherein the reactor pressure is from 400 psig (2758 kPa) to 550 psig (3792 kPa) and the temperature is from l50°F to 160° F (66°C to 71°C).

Claim 18

A process according to any one of claims 11 to 13 wherein the molar ratio of magnesium halide to aluminum halide in the solid catalyst component is from 8:0.5 to 8:3.0.

Claim 19

A process according to claim 14 wherein the ratio is from 8:1 to 8:1.5.

Claim 20

A process according to any one of claims 11 to 15 wherein the molar ratio of magnesium halide to titanium tetrahalide in the solid catalyst component is from 8:0.4 to 8:1.

Claim 21

A process according to claim 16 wherein the ratio is from 8:0.4 to 8:0.6.

Claim 22

A process according to any one of claims 11 to 17 wherein the trialkylaluminum content of the co-catalyst mixture is from 40 to 60 mol %.

Claim 23

A process according to any one of claims 11 to 18 wherein the A1:Ti ratio is from 90:l to 300:l.

Claim 24

A process according to any one of claims 11 to 19 wherein the hydrogen is present in an amount of from 1.2 to 2.5 mol % based on the total monomer feed to the process.

Claim 25

A process according to any one of claims 11 to 20 which is carried out under continuous conditions at an average residence time of from 1 hour to 3 hours.

Claim 26

A process according to any one of claims 11 to 21 wherein the solids content of the reactor slurry is from 30 wt % to 60 wt %.

Claim 27

A process according to any one of claims 11 to 22 wherein the hydrogen concentration is increased and the ethylene concentration is increased to provide a constant viscosity product.