Polyester cord bonding

Thermosets A number of thermosets have been used as adhesives. Phenolic resins were used as adhesives by Leo Baekeland in the early 1900s. Phenolic resins are still used to bind together thin sheets of wood to make plywood. Urea resins have been used since 1930 as binders for wood chips in the manufacture of particle board. Unsaturated polyester resins are used for body repair and PUs are used to bond polyester cord to rubber in tires, and vinyl film to particle board, and to function as industrial sealants. Epoxy resins are used in the construction of automobiles and aircraft and as a component of plastic cement. 

Unsaturated polyester resins have replaced lead for auto body repair, and polyurethanes (PUs) are being used to bond polyester cord to rubber in tires, to bond vinyl film to particleboard, and as industrial sealants. Epoxy resins are used in automotive and aircraft construction and as a component of plastic cements. 

The pecan pith extract was the best of the tannin extracts examined in bonding to polyester cord. Pullout forces using this extract to totally replace resorcinol were nearly twice as high as in the standard dip. The purified pine bark extract also gave very good results. One commonality in these two extracts... 

Condensed tannins have considerable promise as substitutes for resorcinol used in resin formulations for bonding of nylon or, particularly, polyester cord to rubber. Although much more work needs to be done, preliminary results suggest that refinement of extract properties and adhesive formulations could lead to a large, high-value market for condensed tannin extracts. 

The commercial polymers have molecular weights of up to 100,000 g/mol and ratios of primary-.secondary tertiary amino groups of 1 2 1. They are used as adhesives (e.g., bonding polyester cord to rubber), paper additives, etc. Quaternized poly(ethylene imines) form water-soluble polycations and are used as flocculants in the processing of tap water. 

The nature of the fiber plays the most important role in RFL treatment of tire cords. We know that rayon and nylon cords are easy to bond to rubber by RFL treatment, but polyester cord is extremely difficult. This can be attributed to the nature and structure of the fiber. 

Adhesion. Commercially available 1- or 2-coat adhesive systems produce mbber failure in bonds between ethylene—acryflc elastomer and metal (14). Adhesion to nylon, polyester, or aramid fiber cord or fabric is greatest when the cord or fabric have been treated with carboxylated nitrile mbber latex. 

The carcass or body ply of the tire is made up of fabric yams, typically of steel, nylon, rayon, or polyester, twisted into parallel weft-less cord layers known as plies. These plies are loaded with NR-based compound loaded with adhesion promoters to generate a bond between the cord surface and other tire components. 

Condensed Tannins as Substitutes for Resorcinol in Bonding Polyester and Nylon Cord to Rubber... 

Materials. Two types of standard tire cord obtained from Gen Corporation were used in this investigation polyester, 1300/3, and nylon 66, 1260/3. The rubber composition to which the adhesively dipped cords were bonded had the following composition in parts by weight styrene-butadiene rubber (SBR) 1502, 100 N330 carbon black, 50 zinc oxide, 5 stearic acid, 0.5 sulfur, 1.7 2-morpholinothio-benzothiazole, 2. Master batches were mixed 7 min in a 350-ml Brabender Plasticorder, and curatives were added on a cool two-roll mill. Cure characteristics at 155 °C were determined with an oscillating disc rheometer (ASTM D 2084). The time to reach 90% of the final cure state was 23 min, and the Shore A hardness of the final vulcanizate was approximately 60. 

The production of tyres is among the most important of Automotive applications of adhesion. A modern steel-belted radial tyre contains several reinforcing materials, such as polyester and steel cords. The adhesion of the rubber compound to these cords is of critical importance for the performance and safety of the tyre. Other aspects of Rubber to metal bonding - applications are treated in other articles (see Rubber to metal bonding - basic techniques) here, the adhesion of rubber to the steel cords is discussed. 

Similar high-quality rubber-to-textile adhesion can be obtained with glass and polyester woven fabrics. Also corded fabric (e.g. tyre cord) reacts in a similar manner to give bond strength breaks within rubber (R-R) when diisocyanates, such as MDI, are used as adhesive treatments. 

Hamed G R, Chung K H, Hemingway R W (1989) Condensed tannins as substitutes for resorcinol in bonding polyester and nylon cord to rubber. In Hemingway R, Conner A H (eds) Adhesives from renewable resources. ACS Symp Ser Washington DC 242-253... 

Tire Cord Dip. Tire cord adhesives is another important outlet for latexes. A basic formulation is given in Table 4. The latex is mainly a vinyl pyridine (VP) type. Depending on the fiber to be bonded, the VP latex can be diluted with hot SBR or nonagglomerated cold SBR latex. The dilution depends on the difficulty of bonding the different fibers. Rayon was easy to bond to the carcass and did not require VP latex. Substitution of rayon by nylon and polyester tire cords necessitated the development and use of VP latex. 

The tire cord fabric is pulled of woven fabric and passes through an impregnating bath with a resorcinol-formaldehyde-latex solution that improves the adhesiveness on the rubber. This impregnating is sufficient for viscose and polyamide, but polyester and aramid have to be pretreated additionally with bonding agents based on epoxy resin. 

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