CROSSLINKED THERMOPLASTIC ELASTOMERIC INSULATION

Abstract

The present invention refers to an expanded polymeric material which consists of at least 150 phr, preferably at least 180 phr, but less than 500 phr ingredients in total, comprising 100 phr of at least two polymers, of which at least 40 phr is at least one polyolefin homopolymer and at least 20 phr is at least one styrene butadiene thermoplastic elastomer (TPE-s), the process of manufacturing such a material and the use of such a material.

Claims

1. An expanded polymeric material which consists of at least 150 phr, preferably at least 180 phr, but less than 500 phr ingredients in total, comprising 100 phr of at least two polymers, of which at least 40 phr is at least one polyolefin homopolymer and at least 20 phr is at least one styrene butadiene thermoplastic elastomer.

2. The material according to claim 1, wherein the styrene butadiene thermoplastic elastomer and the polyolefin homopolymer sum up to at least 80 phr.

3. The material according to claim 1, wherein the polyolefin homopolymer is at least one polyethylene homopolymer, preferably a low density polyethylene homopolymer.

4. The material according to claim 3, wherein the polyolefin homopolymer has a melt flow rate of <5 g/10 min, preferably <3 g/10 min at 190 C. and 2.16 kg according to ISO 1133.

5. The material according to claim 1, wherein the styrene butadiene thermoplastic elastomer is at least one linear styrene block copolymer, preferably SBS, SIS, SEBS or SEPS, especially preferred are SEBS or SEPS.

6. The material according to claim 5, wherein the styrene butadiene thermoplastic elastomer has a polystyrene content35% wt., preferably 25% wt., especially preferred 20% wt. according to ASTM D5775.

7. The material according to claim 1, which is crosslinked by a crosslinking system, preferably a peroxide based crosslinking system, especially preferred dicumyl peroxide.

8. The material according to claim 1, comprising at least 20 phr, preferably at least 40 phr of at least one inorganic filler having a surface area20 m.sup.2/g, preferably 10 m.sup.2/g according to BET (DIN ISO 9277).

9. The material according to claim 8, wherein the inorganic filler releases water and/or carbon dioxide and/or carbon monoxide at temperatures above 200 C.

10. The material according to claim 1, comprising at least one chlorinated and/or brominated flame retardant, preferably a flame retardant having a glass transition temperature, softening point or melting point<200 C., preferably <160 C., especially preferred <120 C.

11. The material according to claim 10, wherein the flame retardant is at least one polymeric flame retardant, preferably a brominated polyphenyl ether or brominated epoxy polymer.

12. The material according to claim 1, comprising at least one synergist for the halogenated flame retardants, preferably antimony and/or zinc based materials, especially preferred antimony trioxide and/or zinc stannate.

13. The material according to claim 1, which is expanded to a density of <40 kg/m.sup.3, preferably <35 kg/m.sup.3, especially preferred <30 kg/m.sup.3 according to DIN EN ISO 845.

14. The material according to claim 1, which has a closed cell structure of <5.0%, preferably <2.5% determined by vacuum water absorption according to ASTM D 1056.

15. The material according to claim 1, having a water vapor transmission value of 2000, preferably 5000 according to EN 13469/EN 12086.

16. A process for manufacturing the material according to claim 1, wherein the polymeric material is expanded by decomposition of a chemical blowing agent, preferably of nitroso type, azo type and/or aromatic hydrazide type, especially preferred azodicarbonamide, wherein the amount of the chemical blowing agent is higher than 11% wt., preferably over 13% wt.

17. The material according to claim 1, which is flame retardant according to ASTM E84/CAN ULC S 102 requirements for Class A (25/450), preferably 25/50.

18. The use of the material according to claim 1 for thermal and/or acoustic insulation.

Description

EXAMPLES

[0058] The following examples and comparative examples have been produced in a two-step production process, comprising: [0059] 1. mixing and shaping in an extruder and [0060] 2. expansion and crosslinking in a hot air oven line.

[0061] The extrusion has been performed on a single screw vacuum extruder providing raw unexpanded sheets and tubes. Those sheets and tubes have been crosslinked and expanded simultaneously in a hot air oven cascade of three ovens to sheets of 25 mm wall thickness and tubes of 25 mm wall thickness and 22 mm inner diameter.

[0062] Table 1 lists the raw materials used for the components.

TABLE-US-00001 TABLE 1 Raw materials Chemical Name Trade Name Supplier LDPE DOW LDPE 450E DOW Chemical Company SEBS Kraton G 1657 M Kraton Polymers SEPS Septon 2004 Kuraray Europe GmbH Magnesium hydroxide Magnifin H5 Martinswerk GmbH Calcium carbonate Hubercarb M6 Huber Carbonates, LLC Dicumyl peroxide Luperox DCP Safic-Alcan Azodicarbonamide Microfine ADC- HPL Additives Limited 3202 Tetrabromobisphenol A AP1968 Everkem srl Phosphonate SMC 688 Special Materials Company Hindered amine Flamestab NOR 116 BASF SE Antimony trioxide Triox Produits Chimiques de Lucette Zinc stannate ZB 467 Great Lakes Solutions
Table 2 gives an overview about the tested materials, available product range and their basic make-up. Apart from Climaflex (26024, means wall thickness of 26 mm and inner diameter of 24 mm), all materials were available as tubes in 25 mm wall thickness and 22 mm inner diameter. Climaflex and Tubolit DG-B1 were not available as sheets. Materials marked with an * are comparative examples, the other materials are innovative examples.

TABLE-US-00002 TABLE 2 Comparative and innovative examples No. Name Polymer Material group Range 1* Kaiflex KKplus NBR/PVC FEF Tubes & sheets 2* Aerocel AC EPDM FEF Tubes & sheets 3* Climaflex LDPE PEF Tubes only 4 Tubolit DG-B1 LDPE PEF Tubes only 5* LDPE Tubes & sheets 6 LDPE/SEBS Tubes & sheets 7 LDPE/SEBS Tubes & sheets 8 LDPE/SEBS Tubes & sheets 9 LOPE/SEBS Tubes & sheets 10 LOPE/SEPS Tubes & sheets

TABLE-US-00003 TABLE 3 Make-up of the innovative examples and comparative examples 5, 6 and 7. 5* 6* 7* 8 9 10 LDPE 100 90 70 70 60 70 SEBS 10 30 15 40 SEPS 15 30 Magnesium hydroxide 35 10 Calcium carbonate 40 10 40 Dicumyl peroxide 1 1 1 1 1 1 Azodicarbonamide 18 18 18 26 27 30 Tetrabromobisphenol A 15 20 Phosphonate 20 Hindered amine 2 Antimony trioxide 3 1 Zinc stannate 3 3 119 119 119 185 198 205 (unit: phr)

[0063] Table 4 presents the physical and flammability test results of the different materials. The SBI test has been performed on tubes, ASTM E84 tests have been performed on sheets (if available). Flexibility of the different materials was compared for the same wall thickness and classified from 1 (best flexibility and bendability) to 5 (worst flexibility and bendability).

TABLE-US-00004 TABLE 4 Technical performance/test results Density temperature [W/m*K Fire [kg/m.sup.3] SBI [tubes, application at 0 C.] classification DIN EN Flexibility 25x022] range [tubes] DIN EN WVT value [sheets] No. ISO 845 [rating]* EN 13501-1 EN 14707/EN 14313 ISO 8497 EN 13469 ASTM E 84 1* 52 1 B.sub.L-s3, d0 50 C.-110 C. 0.033 10.000 10/250 2* 56 2 D.sub.L-s2, d0 50 C.-150 C. 0.035 5.000 25/50 3* 27 4 C.sub.L-s1, d0 0 C.-100 C. 0.036 4* 25 5 D.sub.L-s3, d0 0 C.-100 C. 0.044 2000 5* 33 5 E 0.040 2000 60/20 6* 30 4 E 0.039 3000 55/25 7* 29 2 E 50 C.-110 C. 0.038 3000 50/20 8 26 2 D.sub.L-s2, d0 50 C.-110 C. 0.035 5000 25/45 9 28 1 CL-s1, d0 50 C.-110 C. 0.034 7000 20/15 10 24 1 BL-s2, d0 50 C.-120 C. 0.033 8000 15/40 *1 = best, 5 = worst flexibility