Paper phenol formaldehyde resins

Nitrile rubber is compatible with phenol-formaldehyde resins, resorcinol-formaldehyde resins, vinyl chloride resins, alkyd resins, coumarone-indene resins, chlorinated rubber, epoxies and other resins, forming compositions which can be cured providing excellent adhesives of high strength, high oil resistance and high resilience. On the other hand, NBR adhesives are compatible with polar adherends such as fibres, textiles, paper and wood. Specific formulations of NBR adhesives can be found in [12]. 

A reaction vessel explosion at BASF s resins plant in Cincinnati (July 19, 1990) killed one and injured 71. The BASF facility manufactures acrylic, alkyd, epoxy, and phenol-formaldehyde resins used as can and paper-cup liner coatings. The explosion occurred when a flammable solvent used to clean a reaction vessel vented into the plant and ignited. The cleaning solvent that was not properly vented to a condenser and separator, blew a pressure seal, and fdled the 80-year-old building with a white vapor cloud. 

Phenol-formaldehyde resins are the oldest thermosetting polymers. They are produced by a condensation reaction between phenol and formaldehyde. Although many attempts were made to use the product and control the conditions for the acid-catalyzed reaction described by Bayer in 1872, there was no commercial production of the resin until the exhaustive work by Baekeland was published in 1909. In this paper, he describes the product as far superior to amber for pipe stem and similar articles, less flexible but more durable than celluloid, odorless, and fire-resistant. ° The reaction between phenol and formaldehyde is either base or acid catalyzed, and the polymers are termed resols (for the base catalyzed) and novalacs (for the acid catalyzed). 

In the meantime another development had decisively altered the outset situation plastics had been discovered and synthesized, among them also some acid-stable ones such as phenol-formaldehyde resin or poly(vinyl chloride) (PVC). These opened up new possibilities cellulose papers could be impregnated with phenol-formaldehyde resin solution and thus rendered sufficiently acid-stable, and sintered sheets from PVC powder were developed. Independent separators producers were founded, combining knowledge of the chemical industry with experience of the battery industry and thus accelerating the development process. 

Several other papers have appeared in the literature describing hyperbranched poly(siloxysilane)s [103], poly(amine)s [104], poly(phenylene sulfidejs [105], polycarbosilanes [106], phenol-formaldehyde resins [107], poly (aryl ether sul-fone)s [108], poly(alkoxysilanes) [109], and poly(lactoside)s [110] but are not further treated in this survey. 

The polymerization of phenols or aromatic amines is applied in resin manufacture and the removal of phenols from waste water. Polymers produced by HRP-catalyzed coupling of phenols in non-aqueous media are potential substitutes for phenol-formaldehyde resins [123,124], and the polymerized aromatic amines find applications as conductive polymers [112]. Phenols and their resins are pollutants in aqueous effluents derived from coal conversion, paper-making, production of semiconductor chips, and the manufacture of resins and plastics. Their transformation by peroxidase and hydrogen peroxide constitutes a convenient, mild and environmentally acceptable detoxification process [125-127]. 

Since the days of Bakeland many varieties and applications of phenol-formaldehyde resins have been found (1). In this paper we are concerned only with recent applications of functionally substituted phenol-formaldehyde-Novolak resins as applied to lithographic uses for micro-image fabrication. 

The first synthetic plastics were the phenol-formaldehyde resins introduced by Baekeland in 1907 [1], Melamine and urea also react with formaldehyde to form intermediate methylol compounds which condense to cross-linked polymers much like phenol-formaldehyde resins. Paper, cotton fabric, wood flour or other forms of cellulose have long been used to reinforce these methylol-functional polymers. Methylol groups react with hydroxyl groups of cellulose to form stable ether linkages to bond filler to polymers. Cellulose is so compatible with these resins that no one thought of an interface between them, and the term reinforced composites was not even used to describe these reinforced systems. 

Phenol-formaldehyde resins are used in the core assembly and in conjunction with the kraft paper give the characteristic brown colour to the back of the laminate. Features of these resins making them suitable for the purpose include ... 

Core Papers. These commonly are kraft papers of substance weight between 80 and 260 g m-2, usually for impregnation with phenol-formaldehyde resins. 

The natural product comprises veneers of real wood which have been sorted and joined edge-to-edge (for example, by stitching), and bonded under heat and pressure to layers of kraft paper impregnated with phenol-formaldehyde resin. A barrier layer immediately below the veneer is impregnated with melamine-formaldehyde resin and prevents upward migration of the darker phenolic resin. 

In dry conditions decorative laminates will shrink, and in damp they will expand unless suitable precautions are taken the associated movements can give rise to stress cracking of laminates and the bowing of composite boards. Since the phenol-formaldehyde resins are more stable in this respect than melamine-formaldehyde, laminates with phenolic kraft cores have dimensional stability better than those with melamine core papers—and thick laminates incorporating many plies of phenolic core paper are more stable than thin laminates with fewer plies. 

Phenol-formaldehyde resins find numerous applications in such areas as wood composites, fiber bonding, laminates, foundry resins, abrasives, friction and molding materials, coatings and adhesives, and flame retardants (JL). From a specialty chemicals standpoint, they are also used as developer resins in carbonless papers (2.). Conventional methods of preparation involve condensation of a phenol with formaldehyde under either acidic (novolak) or basic (resole) conditions (2). Their typical molecular weight range is from 800-4000 daltons (D) and includes a wide variety of alkyl or aryl substituted phenols (A)- The... 

In an earlier paper (2), we determined that carbohydrates could replace a significant portion of the phenol-formaldehyde resin used for bonding plywood veneer. Carbohydrates from renewable resources such as wood can replace up to 50% of the phenol and formaldehyde in resins formulated under basic conditions without significant loss of bond quality. Two-ply, Douglas-fir-veneer panels bonded with these carbohydrate-modified resins have shear strengths approximately equivalent to those for panels bonded with unmodified phenol-formaldehyde resin. 

The phenol/furfural resins have a greater hydrocarbon solvent tolerance than phenol/formaldehyde resins. This is an advantage in the preparation of resin solutions used for the impregnation of paper or cloth for laminating. 

In the manufacture of bonded insulating materials, the fibers in the fleece shaft or on the conveyor belt are sprayed with an aqueous binder, generally a phenol-formaldehyde resin. The binder content in the bonded insulating material is 3 to 4%. Compaction to the desired density and hardening of the resin binder occurs in a tunnel kiln, through which the fibers are continuously transported on a conveyor belt. The compaction is achieved with a second belt which exerts the required pressure on the upper surface of the continuous sheet. This is often followed by laminating the sheet with e.g. paper, aluminum or plastic foil. Finally the product is rolled up or cut into sheets. 

Red Dye No. 2 was formerly used in food, drugs, and cosmetics but was banned by the US Food and Drug Administration (FDA) in 1976. It is currently used in the United States for dyeing wool, silk, and other textiles as well as paper, wood, and leather products. It is also used as an indicator in hydrazine titrations and is used in color photography and in the manufacture of phenol-formaldehyde resins. Red Dye No. 2 continues to be widely used in food, drugs, and cosmetics in other countries. 

The single largest use for the phenol-formaldehyde resins is in adhesive applications for the production of plywood, chipboard, and particle board. The resin can comprise as much as one-third of the weight of the board, particularly of particle boards, which contributes to a total demand for phenolics in the U.S.A. of over half a million metric tonnes per year. They are also used as the matrix adhesives for the production of several types of grindstones. In combination with paper, woven cotton, glass fiber, etc., components, phenolics contribute to the production of engineering and decorative laminates in the form of rods, tubes, and sheets. The sheet products Arborite and Formica are familiar as the finished surfaces of furniture, bathroom, and kitchen counter tops and other areas where attractive patterns and water resistance are important characteristics. Molded products from phenolics are also important where heat or electrical resistance is required, such as saucepan and toaster handles, switches, and the printed circuit boards used in computers. Recent phenolics production in the U.S.A. has totaled over 500,000 metric tonnes per year, not including fillers [38]. 

Alkylphenols (APs), particularly nonylphenols (NPs) and to a lesser extent octylphenols (OPs), are extensively used for the production of alkylphenol polyethoxylates (NPEOs), a class of non-ionic surfactants that has been largely employed for more than 40 years in textile and paper processing and in the manufacture of paints, coatings, pesticides, industrial detergents, cosmetics and spermicidal preparations, as well as various cleaning products. NPs are also used in the manufacturing processes of many plastics and as monomers in the production of phenol/formaldehyde resins. Smaller quantities of NPs are employed in the production of tri(4-nonylphenyl) phosphite as an anti-oxidant for rubber and in the manufacture of lubricating oil additives. 

A cooperation agreement was made in 1973 between DDS-RO and the Finnish Pulp and Paper Research Institute with the aim to develop products and processes on the basis of membrane filtration of effluents from the pulp and paper Industry. The cooperation with Dr. Kaj Forss section at FPPRI has been very successful. For instance, through an extensive development program UF has been found to be a feasible tool for the preparation of lignin for the Karatex ( ) plywood binder. This adhesive, which is made from ultrafiltered spent sulfite liquor (SSL) or kraft black liquor (KBL), can be used for partial replacement of the much more expensive petroleum based phenol-formaldehyde resin in plywood and other wooden boards. 

Materials from starch crosslinked with melamine-formaldehyde, methylated melamine-formaldehyde, and other amine-aldehyde resins were patented as binders for filter paper,1336 milk filter sheet materials,1338 and aqueous papercoating compositions containing clay, titanium(IV) oxide, butadiene-styrene latex, and calcium octadecanoate.1396,1397 Foams for filters were developed.1398 A heatsetting adhesive was one of the first applications reported for starch crosslinked by urea-formaldehyde and phenol-formaldehyde resins.1331,1340-1342,1347,1372,1399... 

Fillers in Thermosets. Sixty-five years ago, in a paper presented before the American Chemical Society, L. H. Baekeland (55) discussed the usefulness of phenol-formaldehyde resins that, when compounded with wood flour, could be molded. Wood flour, ground nut shells, a-cellulose, or paper add bulk to phenolics, melamine, or urea-formaldehyde resins and make them easier to fabricate and less expensive. 

USE To impart pearly surface to cellulose-base, polystyrene, and phenol-formaldehyde resins, Deutsch er of.. U.S. pat. 2,816,044 (1957 to Brit. Resin Prods.). In heat -sensitive coating for copying paper, Van Dam, (J.S. pat. 2,897,090 (1959 to Anken Chem. Film). To stabilize tolylenedi-amme mixtures against deterioration and discoloration. Powers, US. pat. 3,138,641 (1964 to Mobay). 

Stabisol. Used In surface-coating plastics and copying paper. Imparts pearly surface to cellulose-base, polystyrene and phenol-formaldehyde resins. Used medicinally as an antidiarrheal, antacid and antiulcerative. White solid almost insoluble in H2O, EtOH. Atomergic Chemetals Greeff R.W. Co. Mallinckrodt Inc. Mobay Spectrum Chem. ManuSaduring. 

Phenol-formaldehyde resins filled with organic materials (paper, fabric)... 

The story starts some fourteen years after Baeyer had initiated the first study of phenol-formaldehyde condensation chemistry (which led to the study of phenol-formaldehyde resins and subsequently to calixarene chemistry)" - with the publication of his paper on the condensation of pyrrole and acetone. Baeyer mixed pyrrole, acetone and hydrochloric acid and obtained a white crystalline material, which later proved to be the tetra-pyrrolic macrocycle, me.so-octamethylcalixpyrrole 1. 

Phenol-formaldehyde resin Phenolic resin machine parts Phenol-formaldehyde resin machine-coated paper Starch machinery Aluminum machines, business Polybrominated biphenyl maggot control, agric. 

Thermal Characterization of Kraft Lignin Phenol-Formaldehyde Resin for Paper Impregnation... 

Paper, carbonless copy paper Phenol vapours Phenol-formaldehyde resins Quinine dust... 

Jordan and Vourlas (1975) reported typewriter correction paper to contain phenol-formaldehyde resin. The... 

Nigrosine, 1% petrolatum (Calnan and Connor 1972) Phenol-formaldehyde resin, 10% petrolatum (used in plywood and adhesives for paper) (Malten and Seutter 1984)... 

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