Catalyst masterbatch

Abstract

The present invention relates to a catalyst masterbatch for cross-linking a polyolefin having cross-linkable silicon-containing groups. The catalyst masterbatch includes both of a Brnsted acid and/or Brnsted acid anhydride (A); and a polyolefin (B) containing Brnsted acid and/or Brnsted acid anhydride groups. The invention also encompasses compositions of a polyolefin having cross-linkable silicon-containing groups that include the catalyst masterbatch, use of the catalyst masterbatch in a cross-linking reaction of silicon-containing polyolefins, and a cable layer that includes a polymer made using the catalyst masterbatch.

Claims

1. A catalyst masterbatch for cross-linking a polyolefin comprising cross-linkable silicon-containing groups comprising a Brnsted acid and/or Brnsted acid anhydride (A); and a polyolefin (B) containing Brnsted acid anhydride groups, wherein the Brnsted acid and/or Brnsted acid anhydride (A) are selected from carboxylic acids, carboxylic acid anhydrides, sulphonic acid and/or sulphonic acid anhydrides; wherein (A) is present in an amount of from 0.5 to 20 wt %, and wherein (B) is present in an amount of from 15 to 99 wt % based on the total weight of the catalyst masterbatch.

2. The catalyst masterbatch according to claim 1, wherein component (B) is an ethylene homo- or copolymer or propylene homo- or copolymer.

3. The catalyst masterbatch according to claim 1, wherein component (B) contains Brnsted acid anhydride groups in a total amount of 0.01 to 20 wt. % based on the total amount of component (B).

4. The catalyst masterbatch according to claim 1, wherein the catalyst masterbatch contains Brnsted acid groups and/or Brnsted acid anhydride groups in a total amount of 0.2 to 25 wt. % based on the total amount of the catalyst masterbatch.

5. The catalyst masterbatch according to claim 1, wherein the sulphonic acid comprises the structural element (II) aromatic organic sulphonic acid comprising the structural element (II)
Ar(SO.sub.3H)x (II) with Ar being an aryl group which may be substituted or non-substituted, and x being at least 1.

6. The catalyst masterbatch according to claim 5, wherein the sulphonic acid is selected from the following compounds: (i) an alkylated naphthalene monosulfonic acid substituted with 1 to 4 alkyl groups wherein each alkyl group is a linear or branched alkyl with 5 to 40 carbon atoms with each alkyl group being the same or different and wherein the total number of carbon atoms in the alkyl groups is in the range of 20 to 80 carbon atoms; (ii) an arylalkyl sulfonic acid wherein the aryl group is phenyl or naphthyl and is substituted with 1 to 4 alkyl groups wherein each alkyl group is a linear or branched alkyl with 5 to 40 carbon atoms with each alkyl group being the same or different and wherein the total number of carbon atoms in the alkyl groups is in the range of 12 to 80; (iii) an alkylated aryl disulfonic acid selected from the group consisting of the structure (III): ##STR00003## or the structure (IV): ##STR00004## wherein each of R.sub.1 and R.sub.2 are the same or different and is a linear or branched alkyl group with 6 to 16 carbon atoms, y is 0 to 3, z is 0 to 3 with the proviso that y+z is 1 to 4, n is 0 to 3, X is a divalent moiety selected from the group consisting of C(R.sub.3)(R.sub.4), wherein each of R.sub.3 and R.sub.4 is H or independently a linear or branched alkyl group of 1 to 4 carbon atoms and n is 1; C(O), wherein n is 1; S, wherein n is 1 to 3 and S(O)2, wherein n is 1.

7. The catalyst masterbatch according to claim 6, wherein the sulphonic acid is selected from compounds of group (ii).

8. The catalyst masterbatch according to claim 7, wherein in the sulphonic acid of group (ii) the aryl group is phenyl and is substituted with 1 to 2 alkyl groups wherein each alkyl group is a linear or branched alkyl with 8 to 25 carbon atoms with each alkyl group being the same or different and wherein the total number of carbon atoms in the alkyl groups is in the range of 12 to 40.

9. The catalyst masterbatch according to claim 5, wherein the sulphonic acid is selected from the following compounds: (ii) an arylalkyl sulphonic acid wherein the aryl group is phenyl or naphthyl and is substituted with 1 to 4 alkyl groups wherein each alkyl group is a linear or branched alkyl with 5 to 40 carbon atoms with each alkyl group being the same or different and wherein the total number of carbon atoms in the alkyl groups is in the range of 12 to 80; or (iv) an alkylated aryl disulphonic acid selected from the group consisting of the structure (III): ##STR00005## or the structure (IV): ##STR00006## wherein each of R.sub.1 and R.sub.2 are the same or different and is a linear or branched alkyl group with 6 to 16 carbon atoms, y is 0 to 3, z is 0 to 3 with the proviso that y+z is 1 to 4, n is 0 to 3, X is a divalent moiety selected from the group consisting of C(R.sub.3)(R.sub.4), wherein each of R.sub.3 and R.sub.4 is H or independently a linear or branched alkyl group of 1 to 4 carbon atoms and n is 1; C(O), wherein n is 1; S, wherein n is 1 to 3 and S(O)2, wherein n is 1.

10. A method for cross-linking a polyolefin with cross-linkable silicon-containing groups (C) comprising adding the masterbatch according to claim 1, to the polyolefin (C) to form a polyolefin composition; and treating the polyolefin composition under cross-linking conditions.

11. A cable layer comprising the catalyst masterbatch according to claim 1.

Description

EXAMPLES

Components Used

(1) EVS:

(2) ethylene-vinyl-trimethoxy silane-copolymer produced in a high-pressure tubular reaction process, having a VTMS content of 1.35 wt. % an MFR2 (ISO 1133, 190 C., 2.16 kg) of 1.0 g/10 min and a density of 923 kg/m.sup.3. Said polymer is commercially available as LE4423 from Borealis AG.

(3) EBA:

(4) ethylene butylacrylate copolymer produced in a high-pressure tubular reaction process, having a butylacrylate content of 17 wt % an MFR2 (ISO 1133, 190 C., 2.16 kg) of 7.0 g/10 min and a density of 924 kg/m.sup.3.

(5) ME0420:

(6) maleic anhydride grafted polyethylene with MFR2 (ISO 1133, 190 C., 2.16 kg) of 1.3 g/10 min and a density of 934 kg/m.sup.3. Said polymer is commercially available as Borcoat ME0420 from Borealis AG.

(7) Polyone 2000-WT-50:

(8) A white colorant commercial available under trade name Polyone 2000-WT-50, (supplied by PolyOne Sweden AB). It contains pigment and additives that is known to impair the sulphonic acids as condensation catalyst HDTMS hexadecyl trimethoxy silane DDBSA Dodecylbenzenesulphonic acid Stearic acid Palmera B 1800, obtained from Avokal GmbH Silica Perkasil 408 PD, a precipitated silica with a high surface area and a fine particle size. obtained from Grace Davison, W. R. Grace & Co.-Conn. G3003: maleic anhydride grafted polypropylene obtained from Eastman
Compounding of the Catalyst Masterbatches (Inventive and Reference Examples)

(9) The catalysts masterbatches were compounded using a BUSS AG co-kneader type PR46B-11D/H1 (50 mm screw) with the concentrations shown in table 1 below

(10) TABLE-US-00001 RE1 RE2 IE3 IE4 IE5 IE6 IE7 ME0420 97 44.5 93 G3003 25.5 23.5 EBA wt % 96.6 93 70.5 47.5 68.5 DDBSA 3.4 3 3 3 3 3 3 stearic acid 4 4 4 4 HDTMS 1 1 1 1 1 1 1 perkasil 408 pd 1 1 1 RE reference example; IE inventive example
Compounding of the Compositions

(11) Tape samples containing 94 parts per weight of EVS, 5 parts per weight of the respective masterbatch and 1 part by weight of Polyone 2000-WT-50 were prepared by meltmixing in a tape extruder (Collin Teach-Line Extruder, Type: E 20 T SCD 15 having the following settings.

(12) TABLE-US-00002 Set Values Temperature [ C.] Extruder Zone Speed Output 1 2 3 4 5 6 [rpm] [kg/h] 60 150 160 170 170 170 30 0.8

(13) The obtained tape samples (with 1.8+/0.1 mm in thickness) were used for crosslinking. The crosslinking degree is determined by hot set elongation.

(14) Crosslinking of inventive compositions was effected by keeping the obtained tape sample in ambient conditions, at 23 C. and 50% relative humidity, and let crosslinking to occur for 7 days.

(15) TABLE-US-00003 RE1 RE2 IE3 IE4 IE5 IE6 IE7 Elongation Break 160 90 53 62 85 47 15 min Remaining 6.9 6.3 6.5 3.5 3.3 5.3 Elongation