Elastomeric compositions providing improved wet grip

Patent metadata

Field	Value
Publication number	US-10793719-B2
Application number	US-201816147672-A
Country	US
Kind code	B2
Filing date	Sep 29, 2018
Priority date	Sep 29, 2017
Publication date	Oct 6, 2020
Grant date	Oct 6, 2020

Abstract

The disclosure relates to elastomeric compositions having improved soft touch feel to skin, and in particular grip, especially during wet/humid conditions. In one embodiment, the compositions are part of a composite system, wherein the compositions are connected, for example bonded, molded, over-molded or co-extruded to a substrate, such as a thermoplastic, wood, glass or metal. The elastomeric composition comprises: (a) one or more copolymers present in an amount of 10 wt. % to 90 wt. %, selected from styrenic block copolymers and isoprene polymers; (b) one or more resins an amount of 2 wt. % to 20 wt. %; and optionally (c) at least one softener, filler, antioxidant or the like present in an amount up to 80 wt. %. The resin is selected from coumarone-indene resin, petroleum hydrocarbon resin, terpene based polymers, styrene-alpha-methyl-styrene resins, rosin derived resins, and mixtures thereof.

First claim

The invention claimed is:

1. An elastomeric composition comprising:
a) from 3 to 50 wt. % of a resin selected from the group consisting of a petroleum hydrocarbon resin, terpene based resins, styrene-alpha-methyl-styrene resins, and copolymers and/or mixtures thereof;
b) a first polymer in an amount of 40-95 wt % based on the total weight of the elastomeric composition, the first polymer selected from the group consisting of:
i) a selectively hydrogenated block copolymer having a general configuration A-B-A, (A-B)n, (A-B-A)n, (A-B-A)nX, (A-B)nX or mixtures thereof,
wherein n is an integer from 2 to 30, and X is a coupling agent residue, and
wherein prior to hydrogenation,
A is a polymer block of one or more mono alkenyl arenes, having a number average molecular weight between 3,000 and 60,000; and
B is a controlled distribution copolymer block of at least one conjugated diene and at least one mono alkenyl arene, having a number average molecular weight of 30,000 to 300,000;
ii) a selectively hydrogenated block copolymer having the general configuration S-E-S, (S-E1) n , (S-E1) n S, (S-E1) n X or mixtures thereof,
wherein n has a value of 2 to 6, and X is a coupling agent residue, and
wherein prior to hydrogenation,
S is a polystyrene block,
E is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a number average molecular weight of from 20,000 to 220,000, and
E1 is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a number average molecular weight of from 20,000 to 220,000;
iii) a homopolymer of isoprene, or a copolymer of isoprene and another conjugated diene and/or an olefinically unsaturated monomer, wherein the copolymer can be of random, tapered, or block structure;
and combinations thereof;

c) a second polymer in an amount of 5-55 wt %, wherein the second polymer is selected from the group of a styrene isoprene styrene (SIS), a styrene-ethylene-butadiene-styrene (SEBS), and combinations thereof, and wherein the second polymer is different from the first polymer;
d) optionally, at least one of a softener, a plasticizer, an antioxidant, a stabilizer, a colorant, and a filler, in an amount up to 80 wt. %; and
e) 0.03-25 wt % of a curing agent, said curing agent comprising a peroxide;
wherein the composition has a static coefficient of friction in wet state of at least 1.2 and a kinetic coefficient of friction in wet state of 1.2.

2. The elastomeric composition of claim 1 , wherein
the first polymer is a homopolymer of isoprene, or a copolymer of isoprene and another conjugated diene and/or an olefinically unsaturated monomer, wherein the copolymer can be of random, tapered, or block structure,
the curing agent further comprises x) sulphur or, sulfur-containing compounds; and y) a co-agent selected from the group consisting of monofunctional-, difunctional- and trifunctional methacrylic monomers; and
wherein the composition is cured at a temperature between 135° C.-185° C. for at least 5 minutes.

3. The elastomeric composition of claim 1 , wherein the composition has a static coefficient of friction in a wet state of at least 1.6 and a kinetic coefficient of friction in wet state of at least 1.6.

4. The elastomeric composition of claim 1 , wherein
the first polymer is a selectively hydrogenated block copolymer having a general configuration A-B-A, (A-B)n, (A-B-A)n, (A-B-A)nX, (A-B)nX or mixtures thereof,
wherein n is an integer from 2 to 30, X is a coupling agent residue, and
wherein prior to hydrogenation,
B is a controlled distribution copolymer block of at least one conjugated diene and at least one mono alkenyl arene, having a number average molecular weight of 30,000 to 300,000; and
each block A is a polymer block of one or more mono alkenyl arenes having a number average molecular weight between 3,000 and 60,000.

5. The elastomeric composition of claim 1 , wherein
the first polymer is a selectively hydrogenated block copolymer having a general configuration S-E-S, (S-E1) n , (S-E1) n S, (S-E1) n X or mixtures thereof,
wherein n has a value of 2 to 6 and X is a coupling agent residue, and
wherein prior to hydrogenation,
S is a polystyrene block,
E is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a number average molecular weight of from 20,000 to 220,000, and
E1 is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a number average molecular weight of from 20,000 to 220,000.

6. The elastomeric composition of claim 1 , wherein the first polymer is a homopolymer of isoprene, or a copolymer of isoprene and another conjugated diene and/or olefinically unsaturated monomer, wherein the copolymer can be of random, tapered, or block structure.

7. The elastomeric composition of claim 2 , wherein the co-agent is selected from the group consisting of ethylene glycol dimethacrylate (EGDMA), diethylene glycol dimethacrylate (DEGDMA), triethylene glycol dimethacrylate (TiEGDMA), 1,3-butylene glycol dimethacrylate (BGDMA), trimethylolpropane trimethacrylate (TMPTMA) triallyl isocyanurate, triallyl cyanurate, diethylene glycol diacrylate, neophenylene glycol diacrylate and mixtures thereof.

8. The elastomeric composition of claim 2 , wherein the curing agent is 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, and the co-agent is trimethylolpropane trimethacrylate.

9. The elastomeric composition of claim 6 , wherein the composition has a tensile strength at break, measured according to ASTM D412, of at least 1000 psi.

10. The elastomeric composition of claim 6 , wherein the composition has a 300% modulus, measured according to ASTM D412, of at least 200.

11. The elastomeric composition of claim 1 , wherein the composition has a Type A Durometer hardness, measured at 30 seconds, of at least 35.

12. The elastomeric composition of claim 1 , wherein the resin is a terpene based resin.

13. The elastomeric composition of claim 1 , wherein the resin is a terpene phenol resin having a Tsp ranging from 85° C. to 160° C., and a hydroxyl number ranging from 5 mg KOH/g to 240 mg KOH/g.

14. The elastomeric composition of claim 1 , wherein the resin is a vinyl aromatic resin having a Tsp from 80° C. to 130° C.

15. The elastomeric composition of claim 1 , wherein the resin is selected from the group consisting of terpene polymers, styrene-alpha-methyl-styrene resins, copolymers thereof, and mixtures thereof.

16. The elastomeric composition of claim 1 , wherein the resin is selected from the group consisting of indene resins, aromatic vinyl polymers, and C9 hydrocarbon resins.

17. An article comprising the elastomeric composition of claim 1 .

18. A composite formed by bonding the elastomeric composition of claim 1 with a substrate by any of bonding, molding or using an adhesive, wherein the substrate comprises a polymer.

19. A method for making an elastomeric composition having improved wet grip, the method comprises:
a) mixing:
i) from 3 to 50 wt. % of a resin selected from the group consisting of a petroleum hydrocarbon resin, terpene polymers, styrene-alpha-methyl-styrene resins, and copolymers and/or mixtures thereof;
ii) 40-95 wt % of a homopolymer of isoprene, or a copolymer of isoprene and another conjugated diene and/or an olefinically unsaturated monomer, wherein the copolymer can be of random, tapered, or block structure;
iii) 5-55 wt % of a styre

Assignees

• Kraton Polymers Llc

Inventors

• Gillen Jason D
• Shah Bhavesh
• Pichereau Jeremie
• Van Der Waal Arwin W
• SMIT Joris

Classifications

• C08L9/00 Primary

  Compositions of homopolymers or copolymers of conjugated diene hydrocarbons · CPC title

• C08L53/025

  modified · CPC title

• C08L2205/035

  containing four or more polymers in a blend · CPC title

• C08L2205/03

  containing three or more polymers in a blend · CPC title

• C08L93/00 Primary

  Compositions of natural resins; Compositions of derivatives thereof (of polysaccharides C08L1/00 - C08L5/00; of natural rubber C08L7/00) · CPC title