Long-fiber-reinforced thermoplastic (LFRTs) is a type of easily mouldable thermoplastic used to create a variety of components used primarily in the automotive industry. LFRTs are one of the fastest growing categories in thermoplastic technologies. Long Fiber Reinforced Thermoplastics (LFT) have excellent mechanical properties and stiffness-to-weight ratio which is of great interest to the automotive industry. These in-line compounding processes for long fiber material offer users more flexibility, as they are able to both compound and process such materials in accordance with their own formulation and also use readymade compounds.
End-uses require greater performance than is attainable with short fiber thermoplastic products and where metal is not a desirable option due to weight or per part costs. LFT composites have gained rapid acceptance as a viable alternative to die castings, metal assemblies, and traditional plastic materials in a vast array of markets, including: industrial equipment, automotive, consumer goods, sports and leisure, and information technology.
PROPERTIES OF LONG FIBER REINFORCED THERMOPLASTICS (LFRT)
Markedly higher mechanical properties
High notched impact strength
Reduced creep
Good stability over broad range of temperature and climatic conditions
NEW DEVELOPMENTS
Because of the large investments that go with the purchase of the required extruder and press for the processing of LFT’s, their application has mainly be limited to the automotive sector. It’s evident that in this way the many opportunities that lie outside the automotive sector are not being utilised.
PROCESS TECHNOLOGY
Long Fibre Reinforced Thermoplastics technology has evolved from Glass Mat Thermoplastic sheets GMT), a technology which impregnates glass fibre mats with thermoplastic resins, to Long Fibre Pre Compounded Pellets (LFT pellets). A thermoplastic resin (often polypropylene) is fed into the twin screw compounding equipment, where it gets melted by shear and heat. A continuous glass fibre rovings is fed through holes in a special barrel section located downstream where the polymer is already in molten state Special elements separate the individual filaments of the glass fibre rovings and mixing elements disperse the fibres homogeneously in the compound, in order to produce a composite material with uniform properties. The homogenized compound is either extruded through a die to make a "log" of material or flows into an accumulator to be injected into a mould. Parts are moulded either by compression moulding or by injection moulding .
GLOBAL MARKET
Global consumption in the long fiber thermoplastics (LFT) market is forecast to reach over 313400 tons by the year 2017, encouraged primarily by myriad applications in the automotive industry. Revival of the auto industry after a recession-induced hiatus has been instrumental in driving growth in the LFT composites market, particularly in the manufacture of reinforced structural and semi-structural automobile parts. Market growth is also driven by huge demand from polypropylene, which remains the most dominant resin category for LFTs. While developed Western countries continue to dominate in terms of sheer size, Asia-Pacific, led by China displays immense potential for rapid future growth.