Polyamides are polymers that possess the repeating units of the amide group as a characterising feature. Polyamides are manufactured via a melt spinning process. Polyamide is very elastic and can be permanently deformed using heat. This attribute is exploited during thermostabilisation fixing (heat setting). The most important polyamides are polyamide 6 and polyamide 6.6.
The ester groups in the macromolecule groups are characteristic for polyester. Esters are created through the chemical reaction of organic acids with alcohols and the elimination of water. Polyester is manufactured via a melt spinning process. Polyester fibres are very resistant against tearing and abrasion. As polyester fibres boast very low moisture absorption properties, its strength when wet is as good as when dry.
Polypropylene belongs to the polyolefin group and is obtained through polymerisation of the propene monomer with the help of catalysers. The PP granules are spun to mono, multifilament and spin fibres via a melt spinning process. The polypropylene fibre is the lightest textile fibre, takes on virtually no water and is very resistant against chemicals. Its reasonable UV resistance can be significantly enhanced by adding UV stabilisers. Polypropylene fibres can be produced and implemented in numerous ways:
MFP (multifilament polypropylene)
Filament yarns comprised of several single filaments with less than 0.1mm diameter are described as multifilament. Filament is the international description for textile fibres with very long “continuous” lengths during the man-made fibre manufacturing process.
PPD (wire filament / monofilament)
Monofilament describes a filament yarn made of a single filament with a diameter of 0.03-0.2mm, spun using single or multiple hole atomisers. Coarser monofilaments are also described as wire filaments.
Foil tapes are small strips cut from film, which are stretched monoaxially before or after cutting.
PP Tex (PP staple fibres)
Staple fibres or spinnable fibres are man-made fibres of limited length that are made into spun yarns. This leads to a woolly surface. PP Tex allows natural fibres to be recreated. They are used in Gleistein’s Hempex® ropes, for example.
Hidden behind the trade names Polysteel / Danline / PowerPlait / PowerLaid is a modified polypropylene comprised of a polyolefin mix. Most of the time this is a biopolymer of polypropylene and polyethylene.
PowerPlus is a modified polypropylene made of a polyolefin mix with the addition of polyester fibres, which are spun onto the polyolefin yarns. The polyester fibres hereby further enhance the product’s resistance to abrasion.
Aramid is the description for aromatic polyamide. They are defined as long-chain synthetic polyamides in which at least 85% of the aramide group is directly bound to two aromatic rings. Aramides are characterised by their high resistance against heat as well as their high strength and a high elastic modulus.
LCP refers to the order of the molecules in the polymer melt. Areas form in the polymer melts in which the rod-like molecules are almost aligned in parallel. If the liquid crystal polymers are spun out to fibres, this results in extremely strong products. Liquid crystal polyester fibres are the type mostly manufactured to date. These fibres are characterised by their high strength, a high elastic modulus as well as low moisture absorption and high resistance against chemicals.
HMPE is a high modulus polyethylene fibre that is a highly crystalline, high performance UHMWPE (Ultra-High Molecular Weight Polyethylene). With its specific gravity of 0.97g/cm3 it is lighter than water and floats. The fibre possesses high strength and a high elastic modulus and is very resistant against abrasion, moisture, UV and chemicals.
PBO is comprised of poly(p-phenylen-2,6-benzobisoxazol) chain molecules. It has high strength and boasts a high elastic modulus and only burns in environments when an artificially-created oxygen content of 68% is exceeded.