阅读说明：本技术 橡胶组合物及其制备方法 (Rubber composition and preparation method thereof ) 是由 N·里德 N·雅吉 J·G·皮舍罗 于 2019-09-10 设计创作，主要内容包括：公开了一种橡胶组合物,其包含按100重量份(phr)二烯弹性体计以下物质的共混物：5-95phr的第一二烯弹性体、5-50phr的氢化的苯乙烯类嵌段共聚物(HSBC)、50-200phr的填料和最多25phr的增塑剂。其中HSBC的熔体流动比为1.0-50.0(根据ASTM D-1238在230℃和2.16kg载荷下测量),肖氏A硬度为40-80(根据ASTM D-2240测量),在1Hz下的DMA峰tanδ温度为0-40℃(根据ASTM D-4065测量),和有序-无序转变温度为200-300℃。所述组合物不包含树脂或增塑剂,或包含小于20phr的树脂或增塑剂。(Disclosed is a rubber composition comprising a blend of, based on 100 parts by weight (phr) of a diene elastomer: 5 to 95phr of a first diene elastomer, 5 to 50phr of a Hydrogenated Styrenic Block Copolymer (HSBC), 50 to 200phr of a filler, and up to 25phr of a plasticizer. Wherein the HSBC has a melt flow ratio of 1.0-50.0 (measured at 230 ℃ and 2.16kg load according to ASTM D-1238), a Shore A hardness of 40-80 (measured according to ASTM D-2240), a DMA peak tan delta temperature at 1Hz of 0-40 ℃ (measured according to ASTM D-4065), and an order-disorder transition temperature of 200-. The composition contains no resin or plasticizer, or less than 20phr of resin or plasticizer.)

1. A tire composition comprising: based on 100 parts of the total diene elastomer,

5 to 95phr of a first diene elastomer selected from: polybutadiene, natural rubber, synthetic polyisoprene, butadiene copolymers, isoprene copolymers, and mixtures thereof;

5 to 50phr of a second diene elastomer comprising a Hydrogenated Styrenic Block Copolymer (HSBC);

50 to 200phr of filler; and

0 to 70phr of a resin, a plasticizer, or a combination thereof;

wherein HSBC has the general formula A-B-A, (A-B-)_n、(A-B-A-)_n、(A-B-A-)_nX、(A-B-)_nX or a mixture thereof, wherein n is an integer from 2 to 30, X is the residue of a coupling agent,

wherein, prior to hydrogenation, each A block is a monoalkenyl arene homopolymer block having a true peak molecular weight of from 5 to 15 kg/mol; each B block is a controlled distribution copolymer block of at least one conjugated diene and at least one mono alkenyl arene and has a true peak molecular weight of 30 to 200 kg/mol; wherein the midblock monoalkenyl arene block index of the HSBC is from 3 to 15%, wherein the monoalkenyl arene block index is the proportion of monoalkenyl arene units on the polymer chain in the block B having two ortho-monoalkenyl arenes;

wherein, after hydrogenation, 0-10% of the arene double bonds have been reduced and at least 90% of the conjugated diene double bonds have been reduced; wherein the midblock poly (monoalkenyl arene) content of the HSBC is 20-50 wt% based on the total weight of the midblock;

and wherein the HSBC has a melt flow ratio of 1.0 to 50.0, measured at 230 ℃ and under a 2.16kg load according to ASTM D-1238; a Shore A hardness of 40-80, measured according to ASTM D-2240; a DMA peak tan delta temperature at 1Hz of 0 to 40 ℃ measured according to ASTM D-4065; and the order-disorder transition temperature is 200-300 ℃.

2. The tire composition of claim 1, wherein the composition comprises 0-20phr of a resin selected from the group consisting of substituted or unsubstituted Cyclopentadiene (CPD) homopolymer or copolymer resin, substituted or unsubstituted dicyclopentadiene (DCPD or (D) CPD) homopolymer or copolymer resin, terpene homopolymer or copolymer resin, rosin-derived resin, rosin ester, pinene homopolymer or copolymer resin, C5 fraction homopolymer or copolymer resin, C9 fraction homopolymer or copolymer resin, α -methylstyrene homopolymer or copolymer resin, (D) CPD/vinyl aromatic copolymer resin, (D) CPD/terpene copolymer resin, terpene/phenol copolymer resin, (D) CPD/pinene copolymer resin, pinene/phenol copolymer resin, (D) CPD/C5 fraction copolymer resin, (D) CPD/C9 fraction copolymer resin, terpene/vinyl aromatic copolymer resin, terpene/phenol copolymer resin, pinene/vinyl aromatic copolymer resin, pinene/phenol resin, C5 fraction/vinyl aromatic copolymer resin, and combinations thereof.

3. The tire composition of any one of claims 1-2, wherein the composition comprises less than 35phr of a plasticizer selected from the group consisting of: aliphatic acid esters, hydrocarbon processing oils, tall oil pitch, modified tall oil pitch, and combinations thereof.

4. The tire composition of any one of claims 1-2, wherein the composition comprises 5-25phr of a plasticizer.

5. The tire composition of any one of claims 1-2, wherein the second diene elastomer is present in an amount of at least 10 phr.

6. The tire composition of claim 1, wherein the HSBC has the general formula (A-B-A)_nX、(A-B)_nX or a mixture thereof, and wherein the coupling efficiency is 30-95%.

7. The tire composition of any one of claims 1-2, wherein the second diene elastomer comprises:

straight chain HSBC with the general formula of A-B-A, (A-B-)_n、(A-B-A-)_nOr a combination thereof and having a total apparent number average molecular weight of from 70 to 150 kg/mol; and

branched chain HSBC of the general formula (A-B-A-)_nX、(A-B-)_nX or a combination thereof and each arm has a total apparent number average molecular weight of from 35 to 75 kg/mol.

8. The tire composition of any one of claims 1-2, wherein each B block has:

terminal regions adjacent to the a block that are rich in conjugated diene units and one or more regions not adjacent to the a block that are rich in mono alkenyl arene units,

10-40 wt% polymerized monoalkenyl arene units,

a styrene block index of less than 10%; and

the vinyl content is at least 40 mol%.

9. The tire composition of any one of claims 1-2, wherein the HSBC has a mid-block vinyl content of 30-90 mol%.

10. The tire composition of any one of claims 1-2, wherein the HSBC has a total poly (monoalkenylarene) content of 30-70 wt%.

11. The tire composition of any one of claims 1-2, wherein the first diene elastomer is end-functionalized with a C-Sn bond, an amino group, a silanol group, a polysiloxane group, or an epoxy group.

12. The tire composition of any one of claims 1-2, wherein the tensile strength of the HSBC is 10-30 MPa.

13. The tire composition of any one of claims 1-2, wherein the HSBC has a rate of change of elastic modulus (ag) over a temperature range of 0-40 ℃ measured according to ASTM1640-99_0℃-40℃) Is-9 to-25 MPa/DEG C.

14. The tire composition of any of claims 1-2, wherein the HSBC has an elongation of 500-.

15. The tire composition of any one of claims 1-2, wherein the first diene elastomer is selected from the group consisting of Natural Rubber (NR), Butadiene Rubber (BR), synthetic polyisoprene rubber, epoxidized natural rubber, polybutadiene rubber, nitrile-hydrogenated butadiene rubber HNBR, hydrogenated styrene-butadiene rubber HSBR, ethylene propylene diene monomer rubber, ethylene propylene rubber, maleic acid-modified ethylene propylene rubber, butyl rubber, isobutylene-aromatic vinyl or diene monomer copolymer, bromo-NR, chloro-NR, brominated isobutylene p-methylstyrene copolymer, neoprene rubber, epichlorohydrin homopolymer rubber, epichlorohydrin-ethylene oxide or allyl glycidyl ether copolymer rubber, epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber, chlorosulfonated polyethylene, chlorinated polyethylene, ethylene, propylene, ethylene, propylene, or propylene, ethylene, or propylene, ethylene-propylene, or ethylene-, Maleic acid-modified chlorinated polyethylene, methyl vinyl silicone rubber, dimethyl silicone rubber, methylphenyl vinyl silicone rubber, polysulfide rubber, vinylidene fluoride rubber, tetrafluoroethylene-propylene rubber, fluorinated silicone rubber, fluorinated phosphane rubber, styrene elastomer, thermoplastic olefin elastomer, polyester elastomer, polyurethane elastomer, polyamide elastomer, and mixtures thereof.

Technical Field

The present invention relates to compositions for tire applications.

Background

Tire treads are generally expected to have excellent traction and handling properties, wet skid resistance, low rolling resistance, and good wear characteristics. These properties depend to a large extent on the dynamic viscoelasticity of the rubber compositions used for the manufacture of the tires.

To improve performance, tire compositions typically contain up to 20phr or sometimes up to 75phr of a resin, such as a resin containing substituted or unsubstituted units derived from a cyclopentadiene homopolymer or copolymer, a terpene-based resin, or a rosin-derived material (including rosin esters or oligoester resins).

There is an interest in reducing costs, i.e., reducing the amount of resin and/or plasticizer used in tire compositions, while still maintaining desirable wet grip and rolling resistance properties.

Summary of The Invention

In one aspect, a tire composition is disclosed. The composition comprises: from 5 to 95phr, based on 100 parts (phr) of the total amount of diene elastomer, of a first diene elastomer chosen from: polybutadiene, natural rubber, synthetic polyisoprene, butadiene copolymers, isoprene copolymers and mixtures thereof; 5 to 50phr of a second diene elastomer comprising a Hydrogenated Styrenic Block Copolymer (HSBC); 50 to 200phr of filler; up to 25phr of a plasticizer; wherein HSBC has the formula of A-B-A, (A-B-A)_nX or (A-B)_nX, wherein n is an integer from 2 to 30 and X is the residue of a coupling agent. Prior to hydrogenation, each A block is a monoalkenyl arene homopolymer block having a true peak molecular weight of from 5 to 15kg/mol, and each B block has a true peak molecular weight of from 30 to 200kg/mol and is at least oneA controlled distribution copolymer block of a conjugated diene and at least one mono alkenyl arene. In certain embodiments, the coupling efficiency is 30-95%; a mid-block monoalkenyl arene block index of from 3 to 15 percent, wherein the monoalkenyl arene block index is the proportion of monoalkenyl arene units in block B having two ortho-monoalkenyl arenes along the polymer chain. After hydrogenation, 0-10% of the aromatic double bonds have been reduced and at least 90% of the conjugated diene double bonds have been reduced. The mid-block poly (monoalkenylarenes) content of the HSBC is 20-70 wt% based on the total weight of the mid-block. The HSBC has a melt flow ratio of 1.0-50.0 (measured at 230 ℃ and 2.16kg load according to ASTM D-1238), a Shore A hardness of 40-80 (measured according to ASTM D-2240), a DMA peak tan delta temperature at 1Hz of 10-40 ℃ (measured according to ASTM D-4065), and an order-disorder transition temperature of 200-. In certain embodiments, the tire composition does not include a resin or a plasticizer, or includes less than 20phr of a resin and/or a plasticizer.

In one aspect, the rubber composition is resin-free, has at least 10phr of Hydrogenated Styrenic Block Copolymer (HSBC), and the tan δ of the composition is within 10% of the tan δ of a composition containing a resin (the amount of plasticizer or resin being equivalent to the amount of HSBC).

In another aspect, the rubber composition, when used in a tire, exhibits at least one wet grip performance or dry handling performance that is at least 3% higher than a rubber composition without HSBC.

Examples