Yarn Fibers

Fabric Type	pH range	Temperature	Characteristics
Polypropylene	2-12	up to 190° F	Offers good tensile strength and abrasion resistance. They perform well in organic and mineral acids, solvents and alkalies. Polypropylene is attacked by nitric and chlorosulphonic acids, sodium and potassium hydroxide at high temperatures and concentrations.
Polyester	2-9	up to 325° F	Offers good resistance to most acids, oxidizing agents and organic solvents. Concentrated sulfuric and nitric acids are the exception. Polyesters are dissolved by alkalies at high concentrations.
Nylon	2-8	up to 250° F	Good tensile strength and alkali resistance but are degraded by mineral acids and oxidizing agents. This reaction is accelerated at high concentrations and temperatures.
Cotton	3-10	up to 225° F	Good abrasion resistance and mechanical strength. It is, however, subject to rot, mildew, and shrinkage.
Acrylic	4-5 *Subject to other variables	260 to 280°F / 125 to 135°C	The resistance of acrylic fibers is excellent in organic solvents, good in oxidizing agents, minerals and organic acids and fair in alkali. Will dissolve in sulfuric acid concentrations
Nomex*	2 – 12	up to 425°F	Resist attack by mild acids, mild alkalies, and most hydrocarbons. Resistance to sulfur oxides above the acid dew point at temperatures above 300°F is better than polyester. Flex resistance is excellent.
Kevlar*	5-7	Max operating temp 300-500°F / 149-260°C (Does not melt until over 800°F / 427°C)	Kevlar (aramid yarn) is chemically stable under a wide variety of exposure conditions; however, certain strong acids and bases can cause degradation, particularly over long periods of time and at elevated temperatures.