Phenolformaldehyde

Acrylic Resins. The first synthetic polymer denture material, used throughout much of the 20th century, was based on the discovery of vulcanised mbber in 1839. Other polymers explored for denture and other dental uses have included ceUuloid, phenolformaldehyde resins, and vinyl chloride copolymers. Polystyrene, polycarbonates, polyurethanes, and acryHc resins have also been used for dental polymers. Because of the unique combination of properties, eg, aesthetics and ease of fabrication, acryHc resins based on methyl methacrylate and its polymer and/or copolymers have received the most attention since their introduction in 1937. However, deficiencies include excessive polymerization shrinkage and poor abrasion resistance. Polymers used in dental appHcation should have minimal dimensional changes during and subsequent to polymerization exceUent chemical, physical, and color stabiHty processabiHty and biocompatibiHty and the abiHty to blend with contiguous tissues. 

The Raymond ring-roll mill with its internal air separation is widely used to pulverize phenolformaldehyde resins. The usual fineness of grind is finer than 99 percent minus 200 mesh. Air at 4°C (40°F) is usually introduced into the mill to limit temperature rise. A typical 3036 Raymond mill using 34 kW (45 hp) will produce better than 900 kg/h (2000 Ib/h) at 99 percent minus 200 mesh. 

An examination has, therefore, been made of the effect of solutions of potassium chloride on the electrolytic resistance of films cast from a penta-erythritol alkyd, a phenolformaldehyde tung oil and an epoxypolyamide varnishPotassium chloride was chosen because its conductivity is well known and unpigmented films were first examined in order to eliminate the complexities of polymer/pigment interaction. 

The first purely Synthetic polymer was the phenolformaldehyde family of synthetic resins discovered by Baekeland in Germany and first produced commercially in 1907. In 1930, polystyrene was first manufactured in Germany. 

Using synthesized diallylsilazanes modification of the properties of some important industrial polymer composites based on phenolformaldehide resins has been carried out. Preliminary investigations showed that synthesized polymers in combination with phenolformaldehyde resins were successfully used as binding-components for polymer/graphite and polymer/carbon black electro-conducting composites. 

Besides the aforementioned, preliminary investigations showed that synthesized oligomers and polymers, in combination with phenolformaldehyde resin, were successfully used as binding component for polymer/graphite electro-conducting composites (ECC) [15, 16], Obtained ECC were recommended for creation of electrode material for electrolytic section and the chemical (fuel) sources of electrical energy (on the basis of analogous material) [16],... 

Schoenberg JB, Mitchell CA Airway disease caused by phenolic (phenolformaldehyde) resin exposure. Arch Environ Health 30 574-577, 1975... 

Novolac epoxy resins are produced by reaction of novolac, a phenolformaldehyde resin, with epichlorohyrin and a base. ... 

Some expl compns, contg C and examined at PicArsn included Illuminating Composition, Sr(N03)2 54, Mg 33, PVC 10, C 3 Ca stearate 1% Squib, NC, (lacquer) 51, KC103 44 C 555 Flare, Mg 44, NaCl04 35, Na202 4, phenolformaldehyde resin 15 graphite 255 ... 

Ordnance practices, the term combustible cartridge case is referred to cases fabricated from fibrous NC and a binder. Such cases produce no residue when fired in a conventional artillery weapon system. The term consumable cartridge case has been reserved for cases prepd from combustible materials other than NC, such as woodpulp or paper impregnated with a phenolformaldehyde resin In each type of case, fungicides, flash reducing agents and gun erosion inhibitors can be incorporated... 

Examples are the sulfonating of polyethylene film with chloro-sulfonic acid (60) the sulfonating of sheets of phenolformaldehyde resin (77) the treatment of a film consisting of polystyrene and polyvinylchloride with concentrated sulfuric acid (4) the sulfonating of films consisting of aliphatic vinylpolymers with chlorosulfonic acid (125) the sulfonating of copolymers of a monovinyl- and a polyvinyl compound (30). Also are used copolymers of aromatic monovinyl-compounds and linear aliphatic polyene hydrocarbons (3) copolymers of an unsaturated aromatic compound and an unsaturated aliphatic compound (76), and of reaction products of poly olefines and partially polymerized styrene (173). 

Concentration Gradient Across a Membrane. J. S. Mackie and P. Meares (88) tested the equation (30), derived by them. They measured the diffusion of five different salts through a homogeneous gel membrane of the sulphonated phenolformaldehyde type. The osmotic flow during diffusion was measured too. For the mobilities in the resin the values in free solution were taken, multiplied with the factors Aa [equation (73)] and Q [equation (78)]. 

Process optimization of the thermal treatment of an ablation polymer material, based on phenolformaldehyde resins, was done by time and temperature, by the application of simplex optimization. 

Figure 28 Typical chronopotentiometric profile of a disordered carbon charged-discharged in Li salt-alkyl carbonate solution. The carbon was a Li doped polyacenic semiconductor (PAS) obtained by heat treatment of phenolformaldehyde resin [348]. Note the high capacity, the sloping potential profile and the hysteresis between the charge and discharge routes. (With copyrights from Elsevier Science Ltd., 1998.)...

Polyvinyl acetals improve the impact resistance of DGEBA resins when employed with Lewis-acid-type curing agents. With phenolformaldehyde curing agents they improve the peel and impact resistance of DGEBA adhesive formulations (Lee and Nivelle, 1967). 

Durez. Trademark of Hooker Chem Corp, for a line of phenolformaldehyde resins and molding compds, also including diallyl phthalate resins... 

Physical effects caused by polyethylene glycol bases include softening and liquefaction in mixtures with phenol, tannic acid, and salicylic acid. Discoloration of sulfonamides and dithranol can also occur and sorbitol may be precipitated from mixtures. Plastics, such as polyethylene, phenolformaldehyde, polyvinyl chloride, and cellulose-ester membranes (in filters) may be softened or dissolved by polyethylene glycols. Migration of polyethylene glycol can occur from tablet film coatings, leading to interaction with core components. 

Plastics Cyanoacrylate, epoxy resins, polyacrylates, phenolformaldehyde resins, polyurethane, rubber additives (thiuram, carbamates)... 

Use Curing of phenolformaldehyde and resorcinol-formaldehyde resins, rubber-to-textile adhesives, protein modifier, organic synthesis, pharmaceuticals, ingredient of highly explosive cyclonite, fuel tablets, rubber accelerator, fungicide, corrosion inhibitor, shrink-proofing textiles, antibacterial. 

The products discussed above touch us in every moment of our lives. We wake in the morning to an alarm clock in a polystyrene case we arise from our polyester blend sheets and slip on a pair of slippers glued with polyurethane glue. We flip the polymethylmethacrylate light switch and walk across a Nylon carpet to the bathroom. Our polymethylmethacrylate toothbrush is sitting on the Formica counter top. It has Nylon bristles. The soap we use to wash our face may be hydrocarbon derived sodium lauryl sulfate. We walk to the kitchen with polyvinyl chloride floors and sit at a Formica table. The polyethylene milk carton is at hand to supply the milk for the cereal stored in the polyethylene bag. It is eaten from a urea formamide bowl. The frying pan has a phenolformaldehyde plastic handle and a Teflon interior coating. 

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