GB2072576A - Ahring a halobutyl rubber to an unsaturated rubber - Google Patents

Ahring a halobutyl rubber to an unsaturated rubber Download PDF

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Publication number
GB2072576A
GB2072576A GB8011051A GB8011051A GB2072576A GB 2072576 A GB2072576 A GB 2072576A GB 8011051 A GB8011051 A GB 8011051A GB 8011051 A GB8011051 A GB 8011051A GB 2072576 A GB2072576 A GB 2072576A
Authority
GB
United Kingdom
Prior art keywords
rubber
parts
halobutyl
unsaturated
layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB8011051A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ExxonMobil Technology and Engineering Co
Original Assignee
Exxon Research and Engineering Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Exxon Research and Engineering Co filed Critical Exxon Research and Engineering Co
Priority to GB8011051A priority Critical patent/GB2072576A/en
Priority to JP5000381A priority patent/JPS56159145A/en
Publication of GB2072576A publication Critical patent/GB2072576A/en
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/04—Interconnection of layers
    • B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B25/00—Layered products comprising a layer of natural or synthetic rubber
    • B32B25/04—Layered products comprising a layer of natural or synthetic rubber comprising rubber as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B25/00—Layered products comprising a layer of natural or synthetic rubber
    • B32B25/18—Layered products comprising a layer of natural or synthetic rubber comprising butyl or halobutyl rubber
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C1/00—Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
    • B60C1/0008—Compositions of the inner liner
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C5/00—Inflatable pneumatic tyres or inner tubes
    • B60C5/12—Inflatable pneumatic tyres or inner tubes without separate inflatable inserts, e.g. tubeless tyres with transverse section open to the rim
    • B60C5/14—Inflatable pneumatic tyres or inner tubes without separate inflatable inserts, e.g. tubeless tyres with transverse section open to the rim with impervious liner or coating on the inner wall of the tyre
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L21/00—Compositions of unspecified rubbers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J123/00—Adhesives based on homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Adhesives based on derivatives of such polymers
    • C09J123/26—Adhesives based on homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Adhesives based on derivatives of such polymers modified by chemical after-treatment
    • C09J123/28—Adhesives based on homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Adhesives based on derivatives of such polymers modified by chemical after-treatment by reaction with halogens or compounds containing halogen
    • C09J123/283—Halogenated homo- or copolymers of iso-olefines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B38/00—Ancillary operations in connection with laminating processes
    • B32B2038/0052—Other operations not otherwise provided for
    • B32B2038/0076—Curing, vulcanising, cross-linking
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
    • C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
    • C08L2666/04—Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Mechanical Engineering (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Polymers & Plastics (AREA)
  • Medicinal Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacture Of Macromolecular Shaped Articles (AREA)
  • Laminated Bodies (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
  • Tyre Moulding (AREA)

Abstract

The adhesion between a layer of a halobutyl rubber and a layer of an unsaturated rubber is improved by interposing a layer of a blend of a halobutyl rubber and an unsaturated rubber in a ratio of from 10 to 90 parts of the halobutyl rubber to 90 to 10 parts of the unsaturated rubber between the two layers and curing the assembly, particularly useful in bonding innerliners, treads and sidewalls to tyre carcass in the manufacture of tubeless tyres.

Description

SPECIFICATION Improved adhesion of halobutyl to unsaturated rubbers Theresent invention relates to improving the adhesion of halobutyl rubbers to unsaturated rubbers. In particular the invention is concerned with improving the adhesion of halobutyl innerliners to a tyre carcass in the production of vehicle tyres.
Tubeless tyre generally consists of an innerliner which must be impermeable bonded to a tyre carcass which is generally a textile or steel wire web which is itself bonded to a steel belt finally covered with the tread compound. It is important that the tread has good wear resistance, good road handling characteristics and good adhesion to the carcass. Similarly it is important that the innerliner be highly impermeable and have good adhesion to the carcass. Generally the tread and tyre carcass are made from unsaturated rubbers such as polybutadiene, natural rubber, polyiosopropene of the styrene/butadiene rubbers. The innerliners are generally made from a halobutyl rubber.
The tyres are made by assembling the various layers in a press where they are heated to cure the rubber and to bond the layers together.
One problem in tubeless tyre manufacture is that in using the above conventional process with a halobutyl innerliner to give improved impermeability the adhesion between the rubbers is critical. It has been suggested that the inner liner may be made of bromobutyl and this has been found to improve the adhesion. But since bromobutyl is more expensive this adds significantly to the cost of the tyre.
It also known to put halobutyl in tread formulations to give improved wet grip and traction but hereagain adhesion between the tread and the tyre carcass and tyre belt is of concern.
We have now found that satisfactory adhesion between halobutyl rubbers and unsaturated rubbers may be achieved more economically by interposing a layer of a blend of a halobutyl rubber and the unsaturated rubber between the two layers and curing the assembly.
The invention further provides a process for the manufacture of tyres comprising assembling a sidewall layer containing a halobtyl rubber and a tyre belt compound with a layer of a blend of from 10 parts to 90 parts by weight of a halobutyl rubber and from 90 parts to 10 parts by weight of an unsaturated rubber therebetween in a press and subjecting the assembly to a pressure and elevated temperature to bond and cure the rubber.
The present invention therefore provides a method of bonding halobutyl rubber cointaining up to 5 weight provides a method of bonding halobutyl rubber containing up to 5 weight % halogen to an unsaturated rubber containing at least five units of unsaturation per 95 units of saturation by interposing a layer of a blend of from 10 parts to 90 parts of a halobutyl rubber and from 90 parts to 10 parts of an unsaturated rubber between the layers of the halobutyl and the unsaturated rubber and curing the assembly.
The invention further provides a process for the manufacture of tyres comprising assembling a sidewall layer containing a halobutyl rubber and a tyre belt compound with a layer of a blend of from 10 parts to 90 parts by weight of a halobutyl rubber and from 90 parts to 10 parts by weight of an unsaturated rubber there between in a press and subjecting the assembly to a pressure and elevated temperature to bond and cure the rubber.
The present invention therefore provides a method of bonding halobutyl rubber containing up to 5 weight % halogen to an unsaturated rubber containing at least five units of unsaturation per 95 units of saturation by interposing a layer of a blend of from 10 parts to 90 parts of a halobutyl rubber and from 90 parts to 10 parts of an unsaturated rubber between the layers of the halobutyl and the unsaturated rubber and curing the assembly.
The invention further provides a process for the manufacture of tubeless tyres comprising assemblin a halobutyl interliner and a tyre carcass with a layer of a blend of from 10 parts to 90 parts of a halobutyl rubber and from 90 parts to 10 parts of an unsaturated rubber and a halobutyl therebetween in a press and subjecting the assembly to pressure and elevated temperature to bond and cure the rubbers.
The invention further provides a process for the manufacture of a layer of a blend of from 10 parts to 90 parts of a halobutyl rubber and from 90 parts to 10 parts of an unsaturated rubber between the tread and the carcass in a press and subjecting the assembly to pressure and elevated temperature to bond and cure the rubbers.
Halobutyl rubber is derived from butyl rubber, By butyl rubber we mean copolymers made from the polymerisation of reactant mixtures having 70 to 99.5 wt.% of an isoolefin having 4 to 7 carbon atoms per molecule, e.g. isobutylene and 0.5 to 30 wt.% of a conjugated multiolefin having 4 to 14 carbon atoms per molecule, e.g. isoprene, piperylene or cyclopentadiene. The resulting copolymer contains 85 to 99.8 wt.% of combined isoolefin and 0.2 to 1 5 wt.% of combined multiolefin. Butyl rubber generally has a viscosity average molecular weight of 20,000 to 500,000, preferably 100,000 to 600,000 and a Wijs iodine No. 0.5 to 50, preferably 1 to 1 5. Expressed on a molar basis the butyl rubber may have incorporated therein 0.2 to 10 mole % of combined multiolefin, preferably 1 to 4 mole %, e.g. about 2 mole %.
Halogenated butyl rubber can be made by halogenating butyl rubber in a solution containing 1 to 60 wt.% of butyl rubber in a substantially inert C5 to C8 hydrocarbon solvent, such as pentane, hexane, heptane, etc. The butyl rubber cement thereby formed is halogeneated with a halogen gas, e.g. chlorine, whereby halogenated butyl rubber and a hydrogen halide are i formed. Halogenated butyl rubber may also be obtained by radical halogenation of butyl rubber using an organic halogenating agent containing the NX group (where X is halogen), e.g.
dichloro hydantion, dibromohydantion and chloro- or bromo succinimide.
The halogenated butyl rubber may contain up to 2 halogen atoms e.g. chlorine or bromine per double bond in the copolymer. In general halogenated butyl rubber contains at least 0.5 wt.% and preferably at least 1.0 wt.% of combined halogen. It usually has a viscosity average molecular weight of between 150,000 and 1,500,000 and a mole unsaturation of between 0.5 and 15%. A typical example of a halogenated butyl rubber is Esso chlorobutyl 10-66, a chlorinated butyl rubber containing about 1.3 wt.% chlorine having about 1.7 mole % unsaturation and a viscosity average molecular weight of about 357,000. The halogenated butyl rubber used in the blend from which the layer is made may be the same or different from that used in the interliner, bromobutyl is preferred although mixtures of halobutyls may be used.
The unsaturated rubber may be polybutadiene, polyisoprene either naturally occuring or synthetic or the well know styrene butadiene copolymer rubbers. These generally contain at least 5 units of unsaturation for 95 units of saturation. The unsaturated rubber used in the layer may be the same or different from that in the layer to be bonded, preferably it is the same.
The blend may be from 10 parts to 90 parts of the halobutyl or mixture of halobutyls and from 10 parts to 90 parts by weight of the unsaturated rubber, preferably 20 to 80 parts of the halobutyl per 80 to 20 parts of the unsaturated rubber more preferably 40 to 60 parts of the halobutyl per 60 to 40 parts of the unsaturated rubber. The thickness of the layer is unimportant but we prefer to use one as thin as possible the minimum being determined by calendering possibilities generally 0.5 mm.
In the production of tyres the layer should be interposed between the rubbers to be bonded and the bonding may be achieved during the normal finishing processes in which the various rubber compositions are cured.
Whilst the present invention is particularly suited to the production of vehicle tyres it may be used in any situation where these two types of rubber must be bonded together such as in the production of conveyor belting.
All the rubber compositions used in the present invention will generally contain the conventional curing additives, fillers, stabilisers etc.
The present invention is illustrated but in no way limited by the following examples in which Compound A was a halobutl rubber or blends of halobutyl or blends of Halobutyl(s) with unsaturated rubbers and further containing fillers and curatives.
Compound B was made with 100 phr unsaturated rubbers, fillers and curatives.
Compound C is prepared based on a mixture of halobutyl rubbers and unsaturated rubbers, fillers and appropriate curatives.
Compound C is applied in between compounds A and B and the whole sandwich structure is then cured.
Example 1 Compound A was Chlorobutyl - 1 00 6PF Carbon Black - 60 Flexon 580 (naphthenic oil) - 8 Stearic Acid - 1 ZnO - 3 Sulphur - 0.5 MBTS - 1.5 (Total 174) Compound B was: Natural rubber - 100 HAF Carbon Black - 50 Dutrex R - 7 Escorez 1101 - 2 Stearic Acid - 2 Nonox DPPD - 1 ZnO - 5 Sulphur - 3 MBT - 0.25 Santacuse MOR - 0.75 (Total Compound C is made by mixing compounds A and B in a ratio of 1/1.
Test specimens are 12.5 cm long, 2.5 cm wide were prepared from calendared layers. Each laminate has a thickness of about 1.5 mm. Insertion on one edge of the specimen of a Mylar sheet leaves the edges free for clamping in the adhesion tester. The composite pads are cured for 30 minutes at 150 C and tested for peel adhesion at room temperature and 1 20 C in an Instron tensometer at a 5 Cm/min jaw separation speed, with the following results Peel adhesion kN/m Room Temperature 1 20 C Base Case 3.5 1.7 (no layer of C present) With Compound C 9.0 2.5 Example 2 Compound B of example 1 was used Compound A2, which is compound A of example 1 but with bromobutyl substituted for chlorobutyl was used.
Compound C2, was a 50/50 blend of compounds A2 and B.
Using the same procedure as in example 1, the following results were obtained Peel Adhesion kN/m Room Temperature 120 C Base Case 14 15 With layer of Compound C2 present 36 65 Example 3 Compounds A and B of example 1 were used with Compound C2 of example 2.
Using the same procedure as in examples 1 and 2 the following adhesion results were obtained.
Peel Adhesion kN/m Room Temperature 1 20 C Base Case 3.5 2.5 (no layer of C2 present) With layer of Compound 26 50 C2 present

Claims (4)

1. A method of bonding halobutyl rubber containing up to 5 weight % halogen to an unsaturated rubber containing at least five units of unsaturation per 95 units of saturation by interposing a layer of a blend of from 10 parts to 90 parts of a halobutyl rubber and from 90 parts to 10 parts of an unsaturated rubber between the layers of the halobutyl and the unsaturated rubber and curing the assembly.
2. A process for the manufacture of tubeless tyres comprising assembling a halobutyl interliner and a tyre carcass with a layer of a blend of from 10 parts to 90 parts of a halobutyl rubber and from 90 parts to 10 parts of an unsaturated rubber and a halobutyl therebetween in a press and subjecting the assembly to pressure and elevated temperature to bond and cure the rubbers.
3. A process for the manufacture of tyres comprising assembling a tread and tyre carcass with a layer of a blend of from 10 parts to 90 parts of a halobutyl rubber and from 90 parts to 10 parts of an unsaturated rubber between the tread and the carcass in a press and subjecting the assembly to pressure and elevated temperature to bond and cure the rubbers.
4. A process for the manufacture of tyres comprising assembling a sidewall layer containing a halobutyl rubber and a tyre belt compound with a layer of a blend of from 10 parts to 90 parts by weight of a halobutyl rubber and from 90 parts to 10 parts by weight of an unsaturated rubber therebetween in a press and subjecting the assembly to a pressure and elevated temperature to bond and cure the rubber.
GB8011051A 1980-04-02 1980-04-02 Ahring a halobutyl rubber to an unsaturated rubber Withdrawn GB2072576A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB8011051A GB2072576A (en) 1980-04-02 1980-04-02 Ahring a halobutyl rubber to an unsaturated rubber
JP5000381A JPS56159145A (en) 1980-04-02 1981-04-02 Improvement of adhesive property of halobutyl rubber to unsaturated rubber

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB8011051A GB2072576A (en) 1980-04-02 1980-04-02 Ahring a halobutyl rubber to an unsaturated rubber

Publications (1)

Publication Number Publication Date
GB2072576A true GB2072576A (en) 1981-10-07

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GB (1) GB2072576A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0089162A1 (en) * 1982-03-12 1983-09-21 Polysar Limited Bonding elastomers
EP0385760A2 (en) * 1989-03-02 1990-09-05 Sumitomo Rubber Industries Limited Pneumatic tyre
EP0475733A2 (en) * 1990-09-13 1992-03-18 Sumitomo Rubber Industries Limited Tubeless pneumatic tyres
EP0527598A1 (en) * 1991-08-09 1993-02-17 Sp Reifenwerke Gmbh Inner lining for tyre
US5886106A (en) * 1996-08-06 1999-03-23 Bayer Aktiengesellschat Halogenated butyl rubbers having a low halogen content
US5889123A (en) * 1996-10-07 1999-03-30 Bayer Aktiengesellschaft Polymer compounds and their use for the vulcanization of halogenated butyl rubbers with a low halogen content

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5559021B2 (en) * 2010-12-10 2014-07-23 東洋ゴム工業株式会社 Method for producing vulcanized rubber laminate and vulcanized rubber laminate

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0089162A1 (en) * 1982-03-12 1983-09-21 Polysar Limited Bonding elastomers
EP0385760A2 (en) * 1989-03-02 1990-09-05 Sumitomo Rubber Industries Limited Pneumatic tyre
EP0385760A3 (en) * 1989-03-02 1991-01-30 Sumitomo Rubber Industries Limited Pneumatic tyre
EP0475733A2 (en) * 1990-09-13 1992-03-18 Sumitomo Rubber Industries Limited Tubeless pneumatic tyres
EP0475733A3 (en) * 1990-09-13 1992-11-25 Sumitomo Rubber Industries Limited Tubeless pneumatic tyres
EP0527598A1 (en) * 1991-08-09 1993-02-17 Sp Reifenwerke Gmbh Inner lining for tyre
US5886106A (en) * 1996-08-06 1999-03-23 Bayer Aktiengesellschat Halogenated butyl rubbers having a low halogen content
US5889123A (en) * 1996-10-07 1999-03-30 Bayer Aktiengesellschaft Polymer compounds and their use for the vulcanization of halogenated butyl rubbers with a low halogen content

Also Published As

Publication number Publication date
JPS56159145A (en) 1981-12-08

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