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In addition, chemical compatibility refers to the container material being acceptable to store the chemical or for a tool or object that comes in contact with a chemical to not degrade. For example, when stirring a chemical, the stirrer must be stable in the chemical that is being stirred. Many companies publish chemical resistance charts.
The chemical resistance of a material or surface can be determined in compliance with ISO 2812 Paints and varnishes – Determination of resistance to liquids – Part 1: Immersion in liquids other than water (ISO 2812-1:2007 [1]); German Version EN ISO 2812-1:2007 or Part 4: Spotting methods (ISO 2812-4:2007 [2]); German Version EN ISO 2812-4:2007.
The PPE blends are characterized by hot water resistance with low water absorption, high impact strength, halogen-free fire protection and low density. This plastic is processed by injection molding or extrusion; depending on the type, the processing temperature is 260–300 °C. The surface can be printed, hot-stamped, painted or metallized.
It is widely used in place of polystyrene owing to its greater thermal resistance. The chains of between 70 and 80% by weight styrene and 20 to 30% acrylonitrile. [1] Larger acrylonitrile content improves mechanical properties and chemical resistance, but also adds a yellow tint to the normally transparent plastic. [2]
COC shows good chemical resistance and barrier to other solvents, such as alcohols, and is very resistant to attack from acids and bases. Electronic properties of COC are in some respects similar to fluoropolymers, most notably a similarly low dissipation factor or tan delta, and low permittivity. It is a very good insulator. [3]
With speed welding, the plastic welder, similar to a soldering iron in appearance and wattage, is fitted with a feed tube for the plastic weld rod. The speed tip heats the rod and the substrate, while at the same time it presses the molten weld rod into position. A bead of softened plastic is laid into the joint and the parts and weld rod fuse.
Repeating unit of polyphthalamide. Polyphthalamide (aka.PPA, [1] High Performance Polyamide) is a subset of thermoplastic synthetic resins in the polyamide family defined as when 55% or more moles of the carboxylic acid portion of the repeating unit in the polymer chain is composed of a combination of terephthalic (TPA) and isophthalic (IPA) acids. [2]
Polymer engineering is generally an engineering field that designs, analyses, and modifies polymer materials. Polymer engineering covers aspects of the petrochemical industry, polymerization, structure and characterization of polymers, properties of polymers, compounding and processing of polymers and description of major polymers, structure property relations and applications.