Plasticizer paraffinic hydrocarbon oils

The difference between plasticizers and tackifiers is somewhat arbitrary and the effect of this difference is described below in the section on Physical Properties. Plasticizers are typically lower in molecular weight and melting or softening point than are tackifiers. Hydrocarbon oils including aromatic, naphthenic, and paraffinic are commonly used with rubber-based adhesives. Phthalates, such as dioctyl phthalate or dibutyl phthalate, are more typically used in small amounts with acrylics. Since plasticizers are usually low molecular weight compounds, there is often more latitude in the chemical types that will be compatible with the base pol5mier because of the contribution from entropy of mixing. 

The increased polarity of the acrylic polymers puts more stringent requirements on the properties of the tackifiers or plasticizers that can be used. The very low polarity additives commonly found in rubber based PSAs are not useful in most acrylic PSA formulations. For example, materials like paraffin waxes, mineral oils, and synthetic hydrocarbon tackifiers have little or no value in most acrylic PSAs. 

Petroleum becomes more or less a plastic solid when cooled to sufficiently low temperatures. This is due to the congealing of the various hydrocarbons that constitute the oil. The cloud point of petroleum (or a product) is the temperature at which paraffin wax or other solidifiable compounds present in the oil appear as a haze when the oil is chilled under definitely prescribed conditions (ASTM D2500, D3117). As cooling is continued, petroleum becomes more solid, and the pour point is the lowest temperature at which the oil pours or flows under definitely prescribed conditions when it is chilled without disturbance at a standard rate (ASTM D97). 

In solvent-borne rubber adhesives, a variety of solvents can be chosen to control drying rate, adjust viscosity and dissolve important ingredients. Resins can be added to improve tack, wetting properties, heat resistance, bond strength and oxidation resistance. The most common resins nsed in rubber-based adhesives are rosins, rosin esters, and terpene, coumarone-indene, hydrocarbon and phenobc resins. Plasticizers and softeners reduce hardness, enhance tack and decrease cost of rubber adhesive formulations. Paraffinic oils, phthalate esters and polybutenes are typical plasticizers. Fillers are not often added to rubber adhesive formulations because they reduce adhesion. However they are sometimes used because they decrease cost and increase solution viscosity. Carbon black and titanium dioxide are also used to provide colour to the adhesives. Clays, calcium carbonate and silicates are also common fillers in rubber adhesive formulations. For water-borne adhesives, typically protective colloid, preservative, defoamers, wetting agents and emulsifiers are included in the formulations. 

Polymeric plasticizers, such as poly(propylene adipate) and poly(propylene sebacate), are non-volatile, non-migratory and resistant to hydrocarbon extraction. However, they are expensive and the compounds are difficult to manufacture. Extender plasticizers are not compatible with PVC but are miscible with plasticized PVC. A processor can use them to replace a part of the more expensive plasticizer content. Examples include chlorinated paraffin waxes, paraffin liquids or oil extracts. 

Waxes. Waxes are a variation of oil molecules, are the solid form of hydrocarbon alkane chains more than about 20 carbons long, and are insoluble in water. These materials are usually amorphous plastic solids at room temperature, very hydrophobic, and can be found in many plants and organisms acting as a waterproof coating. Some natural waxes include beeswax, lanolin, and carnauba. Paraffin wax is typically derived from crude oil for commercial use, although many plant waxes are very similar in composition, a mixture of mostly straight-chain hydrocarbons. 

A variety of plasticizers can be used in adhesives and sealants as to their primary resin type. Paraffinic oils, phthalate esters, and polybutenes are typical plasticizers (Dostal 1990). Plasticizers for natural rubber adhesives, such as mineral oil or lanolin, are used to reduce the cost of the adhesive mass, and have a depressing effect on the peel adhesion (Satas 1999). Phthalates, chlorinated hydrocarbons, and aliphatic hydrocarbons are commonly used as plasticizers in urethane sealants (Dostal 1990). Most of sealants, except for silicones, contain plasticizers in their formulations. Silicone sealants can be plasticized only by low molecular weight silicone oils (Petrie 2000). 

Uses Anti-adherent agent for mold release of plastics to be painted or glued ten-sio-active agent for varnishes, paints maintenance product additive lubricant for small mechanical parts and med. temp. waxing additive in paraffin oils Properties Cl. to si. cloudy, colorless to pale yel. liq. thinnable in hydrocarbons, ketones, esters dens. - 0.90 vise. - 750 mm /s solidification pt. -60 C flash pt. (CC) - 215 C ref. index - 1.449 surface tension = 28 Storage 3 yrs. when stored in original, unopened packaging -20 to 50 C Rhodorsil Oils 70047 V2, V5 [Bluestar Silicones France]... 

Uses Emulsifier for cosmetics, pharmaceuticals, agric, suspension and emulsion polymerization antifog for plastics lubricant, softener for textile fibers Properties Amber vise, liq., mild odor sol. in alcohols, hydrocarbons, natural and paraffinic oils sp.gr. 1.04 vise. 5250 cs HLB 8.0 pour pt, 15 C flash pt. (PMCC) > 150C 100% act. 

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