Resorcinol-formaldehyde latex resins

SRF. [S nectady] Resorcinol formaldehyde preform resin sol n. bonding agent ukd in rubber compds. to improve adhesion resorcinol donor in re-sordncd-formaldehyde latex dips. 

Resorcinol-formaldehyde latex. See Resorcinol-formaldehyde resin... 

Synonyms Resorcinol-formaldehyde latex Resorcinol resin Classification Phenol-formaldehyde resin Definition Thermosetting prepolymer cured by reaction with paraformaldehyde... 

Resorcinol-formaldehyde latex. See Resorcinol-formaldehyde resin Resorcinol-formaldehyde resin CAS 65876-95-1 24969-11-7 Synonyms Resorcinol-formaldehyde latex Resorcinol resin... 

The most common textile bonding compositions are, of course, the RFL (resorcinol-formaldehyde-latex) dips used to adhere tire carcass rubber to cord reinforcing members. A typical RFL composition calls for a latex terpolymer of styrene-butadiene-vinyl pyridine as well as the resorcinol and hexamethylene tetramine. Some natural rubber latex or regular SBR latex may also be added. The R F resin which forms in situ is able to react chemically with rayon by methylol etherification of the cellulose s hydroxyls. Similar reaction is likely with the amide groups of nylon fibers as shown in Figure 7. 

The dip is prepared by dissolving the aminimide and surfactant in water with moderate stirring. The epoxy resin is then added with rapid stirring. The dip is ready for use and stable for 10-14 days. It is applied to the cord in a 1-3 sec dip. This is followed by drying in an oven at about 450 F (depending on cord type and desired properties) for about 45-60 sec. A second cover dip of conventional resorcinol-formaldehyde-latex emulsion is then applied followed by 45 sec drying at 450°F. 

In the 1940s rayon was used almost exclusively in tires. It was difficult to adhere rayon to rubber mechanically because of the smooth surface of the rayon filaments. Fortunately, two Dupont Co. chemists, W. H. Charch and D. B. Maney found that incorporating a resorcinol-formaldehyde thermosetting resin into a rubber latex made a cord adhesive which gave excellent adhesion of rayon to rubber carcass compounds. The same RFL cord adhesive was also used when nylon was introduced as a tire reinforcing material in 1947 and when glass fiber was introduced as belt material in belted bias and radial tires. 

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. 

Tire Cord. Melamine resins are also used to improve the adhesion of mbber to reinforcing cord in tires. Textile cord is normally coated with a latex dip solution composed of a vinylpyridine—styrene—butadiene latex mbber containing resorcinol—formaldehyde resin.. The dip coat is cured prior to use. The dip coat improves the adhesion of the textile cord to mbber. Further improvement in adhesion is provided by adding resorcinol and hexa(methoxymethyl) melamine [3089-11 -0] (HMMM) to the mbber compound which is in contact with the textile cord. The HMMM resin and resorcinol cross-link during mbber vulcanization and cure to form an interpenetrating polymer within the mbber matrix which strengthens or reinforces the mbber and increases adhesion to the textile cord. Brass-coated steel cord is also widely used in tires for reinforcement. Steel belts and bead wire are common apphcations. Again, HMMM resins and resorcinol [108-46-3] are used in the mbber compound which is in contact with the steel cord to reinforce the mbber and increase the adhesion of the mbber to the steel cord. This use of melamine resins is described in the patent Hterature (49). 

A mixture of rubber latex and resorcinol-formaldehyde resin used to treat man-made and synthetic textiles to improve rubber/textile adhesion. 

Application of solubility parameter match is also demonstrated in adhesives for polyester tire cord. Whereas resorcinol-formaldehyde resin is used in conjunction with polyvinylpyridine latex as an adhesive for rayon tire cord, this composition is not suitable for poly (ethylene terephthalate) (PET) cord. However, using hexylresorcinol rather than resorcinol results in a match of the solubility parameters of adhesive and fiber with resultant increased adhesion (21). 

Resorcinol + formaldehyde Melamine + formaldehyde Latex adhesive for tire cord Laminating resin Water Water NH4OH NaOH Atm Ambient Spray dried, or used as a solution Not isolated but used as a solution... 

Methacrylatochromic chloride bonding agent, latex dips Hexamehoxymethylmelamine, Resorcinol-formaldehyde resin bonding agent, NBR Chemlok 205... 

Heucorox Yellow 145 MF, Heucorox Yellow 150 MF. See Iron oxide yellow monohydrate Heveagrip. See Resorcinol-formaldehyde resin Heveasyn PVC Latex. See Polyvinyl chloride Heveatex Acrylic. See Acrylic resin Heveatex Nitrile. See Butadiene/acrylonitrile copolymer... 

Rubber products such as tyres, belts and hose rely on reinforcement by textiles to achieve the required physical properties. To effect reinforcement, textile and rubber must be adequately bonded together, and to promote adhesion, there is a range of treatments to suit most fibre-rubber systems. The adhesion-promoting material (dip) is usually a terpolymer latex of butadiene-styrene-vinyl pyridine (or a blend of SBR and vinyl pyridine), which bonds well to the fibres, together with a resorcinol formaldehyde precondensate, which, on curing, bonds well to mbber a three-dimensional resin network is formed. 

The standard aqueous treatment for textile adhesion is based on resorcinol/formaldehyde resin/latex (RFL) dip systems. A typical formulation for such an adhesive dip is given in Table 9.1. 

Pre-condensed resorcinol-formaldehyde resin, Koppers, Inc. Styrene-butadiene-vinyl pyridine latex, B.F. Goodrich Chemical Co. 

An RFL dip consists of an aqueous resorcinol formaldehyde resin liquid with a ruhher latex. The RF resin is used to achieve good adhesion to the organic fiber substrate whether it be rayon, nylon, or polyester. The rubber latex portion can be a natural rubber latex or a styrene butadiene vinylpyridine (terpolymer) latex or even a neoprene latex. This rubber latex is present to achieve good adhesion with the rubber matrix itself. So the RFL allows good adhesion between the rubber and the textile cord reinforcement whether it is used in the manufacture of passenger tires, truck tires, off-the-road tires, power transmission belts, V-belts, timing belts, or various hose products. 

RFL resorcinol formaldehyde resin plus latex) bonding of tire cord to rubber. 

Latex 571 contains a very high gel polymer which offers high strength films with low permanent set. Latex 571 is primarily used in combination with other latexes and resorcinol-formaldehyde resins for bonding elastomers to fibers and fabrics. 

Amino resin adhesives may also be used to improve bonding between other materials. For example, tire cord is normally treated with a rubber latex to improve adhesion to the vulcanized rubber. The latex dip solution may also contain a resorcinol-formaldehyde resin or an amino resin to improve the bonding. Both urea and melamine resins are mentioned in patents, but melamine-formaldehyde is said to be most effective. 

Most of the aramid adhesive systems initially used were based on a first-step dip of either an epoxide or a blocked polyisocyanate and then a second or top coat of RFL. Wenghoefer in his patent disclosed a somewhat different first step dip which consisted of bis(j3-azido-formyl oxyethyl)isophthalate. After drying, the cord thus treated, was then dipped in a phenolic adhesive and cured at 230 C for 60 seconds. A patent issued to Van Gils uses a one-step dip based on vinyl pyridine latex, trimethylol-phenol, resorcinol-formaldehyde resin, and... 

World production of resorcinol in 1985 was around 25,000t. Resorcinol resins, obtained from resorcinol and formaldehyde, are used as special adhesives in the timber industry and as tackifiers, usually in combination with vinylpyridine latex for steel cord tires. 

The actual ratios of resorcinol to formaldehyde and of resin to rubber solids may be varied within reasonable limits, the generally accepted optimum ratios being between 1 1.5 and 1 2 for the resorcinol to formaldehyde and between 1 5 and 1 7 for the resin to rubber ratio. Within these limits, it is possible to fine tune the RFL formulation to suit the particular rubber compound with which it is to be used. Generally, however, it is more convenient to use a standard dip formulation for most applications, to avoid excessive complexity, while still maintaining perfectly adequate adhesion levels to a wide range of rubber compounds. For most applications, the preferred latex used is a styrene/ butadiene/vinyl pyridine (VP) terpolymer latex. 

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