Melamine fiber adhesion

Adhesion of melamine fiber to rubber matrices Rajeev et al. found that the dry bonding system consisting of resorcinol, hexamethylene tetramine and hydrated silica effectively reinforces EPDM [64], maleated EPDM [118], and nitrile mbber matrices [119]. They observed increase in tensile... 

The polarity of the matrix helps to improve the adhesion between melamine fiber and rubber because of the polar-polar interaction between the fiber and the matrix [118]. The presence of fiber in the absence of bonding system showed only marginal improvement in tensile strength (from 1.5 to 1.6 MPa) in the case of EPDM rubber-melamine hber composites. However, maleated EPDM rubber-melamine hber composites showed more than 50% improvement in tensile strength in the absence of the bonding system [118]. This is because of the presence of maleic anhydride groups, which imparts polarity to the mbber. 

Amino and Phenolic Resins. The largest use of formaldehyde is in the manufacture of urea—formaldehyde, phenol—formaldehyde, and melamine—formaldehyde resins, accounting for over one-half (51%) of the total demand (115). These resins find use as adhesives for binding wood products that comprise particle board, fiber board, and plywood. Plywood is the largest market for phenol—formaldehyde resins particle board is the largest for urea—formaldehyde resins. Under certain conditions, urea—formaldehyde resins may release formaldehyde that has been alleged to create health or environmental problems (see Amino RESINS AND PLASTICS). 

Together, antifreeze, PET, and polyester polymers account for about 98% of the ethylene glycol produced in the United States. It is also used sometimes as a deicer for aircraft surfaces. The two hydroxyl groups in the EG molecule also make EG suitable for the manufacture of surfactants and in latex paints. Other applications include hydraulic brake fluid, the manufacture of alkyd resins for surface coatings, and stabilizers for water dispersions of urea-formaldehyde and melamine-formaldehyde The hygroscopic properties (absorbs moisture from the air) make EG useful as a humectant for textile fibers, paper, leather, and adhesives treatment. 

Wood Composites—these are resin-bonded composite boards where the particles are wood shavings, flakes, chips, or fibers bonded with thermosetting adhesives that can be urea formaldehyde, melamine formaldehyde, phenol formaldehyde, or diisocyanate. In recent years, the markets for OSB and MDF board have been rapidly increasing. Most particle board production uses urea-formaldehyde as a binder that is acid setting. Hence, sodium borates (alkaline) can interfere with the setting. As a result, boric acid has been the major boron compound used as the flame retardant in particle board.28 29 Typically, a loading of 12%-15% of boric acid in MDF is required to meet the ASTM E-84 Class A rating. If sodium borate is used as a flame retardant, phenol-formaldehyde binder, that is compatible with alkaline chemicals, is commonly used. 

This chapter will deal with the chemistry and applications of epoxies, phenolics, urethanes, and a variety of current vogue high-temperature polymers. Applications in fiber-reinforced plastics will be discussed in the individual sections on resin chemistry where appropriate. Separate sections will deal with adhesives and sealants. Adhesives are most important because, as early history demonstrates, they led the way to the application of resins in aerospace. A section is also included on silicone and polysulfide sealants. Although these materials are elastomers rather than resins, no discussion of aerospace polymers would be complete without some mention. Some major thermosetting polymers have been omitted from this review. Among these are the unsaturated polyesters, melamines, ureas, and the vinyl esters. Although these products do find their way into aerospace applications, the uses are so small that a detailed discussion is not warranted. 

Urecdll . [BASF AG] Urea-formaldehyde or melamine-formaldehyde resins for prod, of adhesives for paper processing, binders for granular materials, fiber webs, shoe cap materials, for pj >ermaking. 

A large number of commercially important condensation polymers are employed as homopolymers. These include those polymers that depend on crystallinity for their major applications, such as rylons and fiber-forming polyesters, and the bulk of such important thermosetting materials like phenolics and urea-formaldehyde resins. In many applications, condensation polymers are used as copolymers. For example, fast-setting phenolic adhesives are resorcinol-modified, while melamine has sometimes been incorporated into the urea-formaldehyde resin structure to enhance its stability. Copolyesters find application in a fairly broad spectrum of end uses. 

Chem. Descrip. y-Ureidopropyltrimethoxysilane CAS 23843-64-3 EINECS/ELINCS 245-904-8 Uses Adhesion promoter aiding bond between fillers and reinforcements (e.g., fiberglass, particulates, metals) and various polymers (phenolic, urea-melamine, epoxies, polyamide, PU), for use in glass fiber sizes and finishes, wool insulation resin binders, primers, foundry sand binders, adhesives, sealants, and abrasive grinding wheel binders Features Contains no flamm. or combustible solv. low VOC emissions Properties Lt. straw clear liq. sol. in methanol, ethanol, acetone, toluene, methyl Cellosolve, water m.w. 220 sp.gr. 1.15 b.p. 217-250 C (700 mm Hg) flash pt. (TCC) 99 C ref. index 1.386 100% act. Silquest Y-11597 [OSi Spec.]... 

Uses Adhesion promoter aiding bond between fillers and reinforcements (e.g., fiberglass, particulates, metals) and various polymers (phenolic, urea-melamine, epoxies, polyamide, PU) used in glass fiber sizes and finishes, wool insulation resin binders, primers, foundry sand binders, adhesives, sealants, and abrasive grinding wheel binders low VOC emissions... 

In the case of the melamine-glass cloth laminate, salt water reduces the electric breakdown strength substantially below that of fresh water. The adhesion of the melamine resin to the glass fibers is limited, and salt water is adsorbed at the resin-glass interface by capillarity. 

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