Oils and Plasticizers

Oils and plasticizers, which are solvents, are commonly added to polymer compounds. Plasticizers are usually used to improve the material s processability and softness. Addition of a plasticizer into a compound reduces its melt viscosity and elastic modulus and, if miscible, the glass transition temperature (T ). 

Rubber compoimds often contain nonvolatile hydrocarbon oil mixtures mixed with varying levels of aromaticity. The hydrocarbon oils are derived from petroleum and are usually classified as naphthenic, aromatic, and paraffinic. 

Polar oils have been known as a plasticizing agent for a century to form resinous materials with cotton and phenol-formaldehyde resins. Polyvinyl chloride compounds often contain varying amoimts of polar ester-based oils. Generally, these oils are miscible in the amorphous polymer matrix of the compound. 

Plasticizers for polyvinyl chloride are nonvolatile liquids miscible with the amorphous regions of polyvinyl chloride. These are usually polyesters, and the most important are phthalates. 

The best known plasticizers of these are dibutyl (R = R = C4H9)- and dioctylphthalate (R = R = CgHjy). The dimethylphthalate (R = R = CH3) has been regarded as a solvent and distearylphthalate (R = R = CigH37) is usually described as a lubricant. 

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CH2=CHC = CCH = CH2. a colourless liquid which turns yellow on exposure to the air it has a distinct garlic-like odour b.p. 83-5°C. Manufactured by the controlled, low-temperature polymerization of acetylene in the presence of an aqueous solution of copper(I) and ammonium chlorides. It is very dangerous to handle, as it absorbs oxygen from the air to give an explosive peroxide. When heated in an inert atmosphere, it polymerizes to form first a drying oil and finally a hard, brittle insoluble resin. Reacts with chlorine to give a mixture of chlorinated products used as drying oils and plastics. 

White crystals m.p. 162-164 C. ll can be prepared by the fermentation of sugar with the mould Aspergillus lerreus or by healing citra-conic anhydride with water at ISO C. Electrolysis of the potassium salt in solution gives allene. Itaconic acid is used as a comonomer in plastics its esters are polymerized to lubricating oils and plasticizers. 

A acrylonitrile potassium salts of dispro-portionated resin acids and fatty acid 31 9.5 41 maximum hot-oil and plasticizer resistance asbestos binder, back coatings... 

Acrylonitrile-butadiene rubber (also called nitrile or nitrile butadiene rubber) was commercially available in 1936 under the name Buna-N. It was obtained by emulsion polymerization of acrylonitrile and butadiene. During World War II, NBR was used to replace natural rubber. After World War II, NBR was still used due to its excellent properties, such as high oil and plasticizer resistance, excellent heat resistance, good adhesion to metallic substrates, and good compatibility with several compounding ingredients. 

Solvents. Solvents are added for the same purposes as oils and plasticizers, and additionally may interact with the substrate (e.g. by partially dissolving the substrate surface). Aromatic and polar solvents are the most suitable. 

NBR adhesives are characterized by high resistance to oils and plasticizers, excellent heat resistance and superior adhesion to metallic substrates. 

Solvent wiping. Rubbers tend to swell by application of solvents and the mechanical interlocking of the adhesive is favored. Although chlorinated hydrocarbon solvents are the most effective, they are toxic and cannot be used toluene and ketones are currently the most common solvents. The treatment with solvents is effective in the removal of processing oils and plasticizers in vulcanized mbbers, but zinc stearate is not completely removed and antiozonant wax gradually migrates to the mbber/polyurethane adhesive interface. Table 27.1 shows the moderate increase in adhesion produced in SBR by MEK wiping. 

Fat- and oil-soluble dyes are used on a large scale in a wide variety of industrial sectors. The main fields of application are the coloration of products in the mineral oil and plastics industries, as well as of wax products (e.g., candles, shoe polishes, floor polishes). 

Murray [91] has described a gas chromatographic method for the determination in water of triarylphosphate esters (lmol S-140, tricresyl phosphate, cresol phosphate). These substances are used commercially as lubricant oil and plastic additives, hydraulic fluids and plasticisers. The method involves extraction from the samples, hydrolysis and measurement of the individual phenols by gas chromatography as the trimethylsilyl derivatives. The lower detection limit was about 3ppm. 

Oxidation inhibitor in natural and synthetic rubbers, polyolefin plastics, resins, adhesives, petroleum oils, and plastics. 

Diacetone alcohol [123-42-2] (4-hydroxy-4-methyl-2-pentanone) is an almost odorless ketone alcohol that is weakly acidic as a result of rearrangement to the enol form. It is miscible with water and organic solvents except aliphatic hydrocarbons. It acts as a good solvent for cellulose esters and ethers, alcohol-soluble resins, castor oil, and plasticizers. Poly(vinyl acetate) and chlorinated rubber are partially dissolved or swollen. Polystyrene, poly(vinyl chloride), vinyl chloride copolymers, dam-ar resins, resin esters, rubber, bitumen, mineral oils, ketone resins, and maleate resins are insoluble. Diacetone alcohol is used as a high boiler in stoving enamels to improve flow and gloss. 

First made commercially available in Germany in 1936, this elastomer is officially known as acrylonitrile butadiene, and is usually the product of an emulsion polymerization process that combines the two monomers acrylonitrile and butadiene. However, the polymer can also be made in a solution process, and with a variety of monomers. As a specialty polymer, and even though several commercial brands were available, Buna N (as it was first known) was little used until World War II, when the polymer s unique oil and plasticizer resistance and high heat resistance became very important for transportation products. Nitrile rubber also exhibits exceptional adhesion to metallic surfaces and is compatible with a wide range of additives and compounding ingredients. 

Nitrile polymers used for the manufacture of adhesives generally contain 25% or more acrylonitrile, but in the base polymer the acrylonitrile content can vary from 15% to 50%. Increasing the acrylonitrile content improves the oil and plasticizer resistance and increases the polarity of the compound. However, higher levels of acrylonitrile also increase the hardness and modulus of the polymer, reducing the elasticity of the resulting polymer. Nitrile rubber can be produced by a cold (5°C) or hot (25-50°C) process, with most adhesive polymers produced by the hot process which induces more chain branching. Nitriles can be combined with other monomers in solution polymerization which increases functionality and improves compatibility with other reactive resins like acrylics, epoxies, and polyurethanes. 

In the chemical industry, catalyzers, adsorbing filters, and expanded plastics can be used in the dry form and placed in the path of appropriate fluids or gases. Freeze-dried dyes may also be dispersed in other media, such as oils and plastics. 

PN-EN 665 2000 Resilient floor coverings - Determination of exudation of plasticizers PN-EN ISO 1043-3 2001 Plastics - Symbols and abbreviated terms - Part 3 Plastieizers PN-C-04406 1998 Pigments - General methods of test - Determination of fastness on water, organic solvents, oil and plasticizers... 

There are three basic procedures for mixing rubber compounds in an internal mixer namely, the conventional method, the rapid oil addition method, and the upside-down mix method. Many variations of these three methods are also used to suit the special characteristics of individual formulations and equipment. It is, in general, necessary to add particulate fillers early in the mixing cycle, so that good dispersion is achieved as a result of the high shear stress and high viscosity at the lower temperatures then prevailing. Similarly, the oils and plasticizers which reduce viscosity should be added later. Upside-down procedures and variants of it are attempts to implement these ideas in practice. 

Nitrile rubber, also known as nitrile-butadiene rubber (NBR), is a copolymer of acrylonitrile and butadiene (Fig. 1). As a base polymer for Rubber-based adhesives, it provides a number of specialized properties, which supplement those summarized in the article Rubber-based adhesives typical characteristics. NBR adhesives comprise a range of materials that may differ in proportion of comonomer or may be compounded with other resins. NBR adhesives are characterized by high oil and plasticizer resistance, excellent heat resistance and high adhesion to metallic substrates. 

Viscosity reduction, hardness reduction, reduced modulus and tensile strength and extended gel times result when oils and plasticizers are blended with OH-BD. A 50 phr content of process oil is common and typical properties are shown in Table 12.2. 

A huge variety of other substances, including coal, oil, and plastics, are also made mainly from carbon. 

Effect of Other Compounding Ingredients on Vulcanization. Other ingredients besides the elastomer and the cure system itself influence cure and scorch behavior. Usually the effect of a material on compound vulcanization is dependent upon the pH of the material. Ingredients which are basic in nature tend to accelerate the rate of both scorch and cure, whereas acidic materials exhibit the opposite effect. Reviews of the effect of antidegradants, fillers, process oils, and plasticizers are available (6,14,32,33). 

Polynorbornene, the first metathesis polymer produced in industrial scale, was marketed in 1976 by CdF Chimie under the trade name Norsorex . The monomer is produced by Diels Alder reaction of cyclopentadiene and ethylene and polymerized in n-butanol using an RuCls/HCl catalyst. Norsorex is a very high molecular weight (Mn > 2 x 10 g/mol), thermoplast (rg = 35°C) with approximately 90% trans-dovhXe bonds. The polymer is compatible with high loads of extending oils and plasticizers (up to 700%) and easily vulcanizable. By addition of suitable amounts of plasticizers the polymer is converted into an elastomer (Tg = —60 °C). 

Optical detectors respond more effectively to dense, heavy particulate smoke such as that generated by oil and plastic fires. Optical detectors are of two main types ... 

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