Thermoplastics,milled glass fibers, jet toll milling, toll milling, milled mineral wool, wollastonite, mica.

Application Guide: Thermoplastic Polymers and Compounding

Background:

Thermoplastic Polymers are characterized primarily by their molecular structure and that upon heating, soften and upon cooling harden. Plastic resins are typically customized to meet specific customer applications by adding reinforcements, flame retardants, processing aids and colorants. Reinforcements are used to enhance mechanical properties, such flexural modulus, tensile strength and thermal properties, such as heat deflection temperature.

Products For Selection:	Features	Benefits
Milled Glass Fibers	Short fiber lengths Wide variety of grades	Stiffness; dimensional stability; high flow during molding; more uniform isotropic shrinkage vs. chopped glass Balance of properties to application
Wollastonite	Natural mineral with high purity Needle-like shape Short fibers with narrow diameter	Favorable cost vs. some glass options Recyclability Improved appearance vs. other minerals Improved mechanical strengths vs. other minerals Options for tensile strength and flexural modulus
Muscovite Mica	Natural mineral with high purity Small diameter choices Tough flexible particles Platy shape	Less interference on heat aging Less reactivity Recyclability Processability vs. synthetic options Favorable cost vs. synthetic options Better surface appearance Less brittle and easier to compound vs. other glass options Reduced permeability Warpage and shrinkage control for large, thin parts
Microwool: Processed Mineral Fiber	Complex silicate chemistry Low bulk density Small diameter with long lengths Processed and surface treated in the U.S.	Lower wear on processing equipment Lower weight parts Increased flexural strength and modulus; increased tensile strength; increased HDT; increased dimensional stability Excellent economics

Suggested Loadings:

Product	% By Weight
Microglass	10 - 35
Wollastonite	15 - 40
Muscovite Mica	20 - 40
Microwool	15 - 45
Note: For best shrinkage and warpage results, a frequent recommendation is a blend of mica with either glass or wollastonite. Other mechanical properties have been reported to be improved by combination of a selected fiber reinforcement with a platy reinforcement.

Expected Observations:

Overall increase in mechanical properties. Median particle size can significantly affect tensile strength and flexural modulus. This selection can be a determining factor in deciding importance of elongation versus tensile strength. Platy-shape minerals, such as mica, are very useful in providing uniform shrinkage. The aspect ratio of platy products can play a significant role in increasing flexural modulus. Better mixing methods and mixing speed choices may improve flexural modulus and flexural strength.

Final determination of the suitability of the material for the use contemplated is the sole responsibility of the user. Manufacturer's only obligation shall be to replace such quantity of the product proven to be defective.