High Performance Fillers for superior thermoplastic applications
Modern thermoplastics have to meet many different requirements e.g. in automotive industry. The polymers alone could not meet the requested demands. For this reason they are reinforced with high quality, functional fillers based on acicular wollastonite, platelet kaolin or platelet mica (muscovite and phlogopite) and granular wollastonite. These High Performance Fillers make a crucial contribution to improve the mechanical and thermal properties of the compounds. Functional fillers result in polymer systems and with it in the finished part in e.g. increased scratch resistance, reduzed mechanical and thermal distortion, and better tensile strength and tensile modulus with constant high impact strength.
Polypropylene is used in different applications. Parts made by injection moulding for electronic engineering, for automotive and white goods are produced from polypropylene. In the last decade, the automotive industry as increasingly turned to polypropylene as a material for making large spare parts, such as bumpers and interior consoles, from these compounds.
- TREMIN® reinforced Polypropylene-Compounds
In polypropylene systems the very good reinforcing properties of surfacemodified, needle-like wollastonite TREMIN® 939 have been successfully used for years. TREMIN® 939 is the preferred product series because compounds with the following properties could be produce:
• excellent scratch resistance on account of the high hardness of TREMIN®
• very good impact strength combined with high rigidity
• high heat deflection temperature
• low shrinkage of parts because of the low coeffiecent of thermal expansion of TREMIN® an important requirement of „Zero-Gap-Design“
Due to the surface treatment of TREMIN® 939 it is easy to mix with the polymer.
Plated MICA muscovite and TREFIL® phlogopite improved remarkable the thermal and
mechanical features of polypropylene/polyethylene compounds. This fillers effect:
• significant reduction of shrinkage in both dimensions
• improvement of heat distortion sensitivity
• enhanced tensile strength and tensile modulus
• enhanced rigidity with constant viscosity
Polyamide 6 and Polyamide 66 are the most commonly employed engineering plastics in the world. Their popularity rests on their high thermostability, high hardness and rigidity. Polyamide 6 is additionally characterized by good damping. These mechanical properties are determined to a large extent by the fillers employed.
TREMIN® wollastonite for PA-Compounds
- Short-needle, aminosilane-coated wollastonite flours TREMIN® 283 have been successfully used for many years as functional fillers for polyamides. With acicular wollastonite TREMIN®939 the rigidity of the compound is still higher. The content of these fillers in the compounds is between 20 and 40 wt.%. Polyamides reinforced in this way offer a range of different possibilities for the design of low warpage, rigid mouldings. They are used in e.g. wheel covers, air filter housings and electrical appliance parts. TREMIN® reinforced compounds are characterized by:
• excellent rigidity
• enhanced resistance to heat deflection
• excellent dimensional stability with TREMIN® 283
• high impact strength
• outstanding paint adhesion
The use of surface treated TREMICA® muscovite and TREFIL® phlogopite affects the mechanical and thermal features in polyamide-compounds in the following way:
• enhanced tensile strength
• increased rigidity
• reduced shrinkage
• better shrinkage isotropy
• distinct reduzed heat-distortion sensitivity
Polyethylene-/ Polypropylene films: SIKRON® micronized cristobalite as antiblocking additive
The High Performance Fillers SIKRON® cristobalite are qualified as antiblocking additive for transparent LDPE/PP-films, because of their refractive index nd1,48 and their grain size distribution. Cristobalite is a high temperature modification of quartz. It is made out of pure silica by heating it up to 1.500°C in a rotary furnace. As a result of this calciningprocess the refrative index is modified. Micronized cristobalite is free of coarse grains, a precondition for the production of smooth film surfaces and a failure-free production. With SIKRON® cristobalite there is the possibility to produce:
• transparent films by reason of the refractive index
• non adhesive films
• food films, because cristobalite is chemically inert
• films with smooth and symmetrical surface
In addition SIKRON® absorb infrared radiation in the wave length of 7-14 mm. With it transparent films for agricultural purposes with reduzed heat emission are producible.