Most people will not have heard of it, but the chances are good that the mineral can be found in the vehicles they are driving. In this edition of Dawn Revette, Product and Marketing Specialist, NYCO Minerals tells the readers of Automotive Industries more about the material.
Wollastonite or calcium metasilicate (CaSiO3) is a naturally occurring industrial mineral that has an acicular (needle-like) structure. Because of this feature, it is an ideal reinforcement for polymer composites and applications. The surface of the wollastonite can also be treated with various silanes and coupling agents to further enhance mechanical properties and improve processing.
Automotive Industries (AI): What are the uses?
Revette: NYCO’s wollastonite products are used in a variety of polymer composites from automotive interior’s (instrument panels, hard trim composites to exterior applications (such as fenders, body side mouldings, spoilers, fascias, mirror housings, roof racks and door handles) to under the hood (engine covers, HVAC, fan shrouds, blades & air cleaner housings). Potential uses for the material in automobiles include soft thermoplastic Polyolefins and thermoplastic Elastomers for improved scuff and mar resistance. We also see an increase in the material being used as a partial or full replacement for milled and chopped glass in thermoplastics, engineering alloys and Thermoset composites for improved surface appearance and reduced compounding/unit costs.
AI: What advantages does it offer to manufacturers over more conventional materials?
Revette: It varies per polymer system and application but overall, the advantages of NYCO?s wollastonite in plastics consist of the following:
– Improved dimensional stability
– Heat sag resistance
– Increased flexural strength
– Excellent balance in stiffness and impact
– Comparable shrinkage at lower loadings
– Improved mar, scratch and gouge resistance
– Lower coefficient of linear thermal expansion (no gap)
– Improved heat distortion temperature
– Improved Tortional shear modulus
– Improved creep resistance
– Class A surface appearance / E-coat compatible
– Non toxic, odourless material
– Improved melt strength of the polymer
AI: What are the reserves of the material?
Revette: NYCO has over 100 million tons of reserves between their ore deposits in Willsboro, New York and Hermosillo, Mexico.
AI: Is the material suitable for recycling?
Revette: NYCO products are recyclable depending on the compounded base polymer and finished composite.
AI: What technological back-up is there for the material?
Revette: NYCO provides full technical support and maintains partnership alliances at the end-user, co-supplier, OEM and certification / sponsorship levels.
AI: What logistical structures are in place to get the raw material to potential users?
NYCO has an extensive worldwide agent / distributor network for warehousing materials worldwide for customer just-in-time delivery. NYCO also maintains a sales office in Brussels, Belgium supported by highly skilled plastic product managers.
AI: How do its costs compare with conventional plastics and metals?
Revette: NYCO products are traditionally lower in cost then the base polymer when taking into account the improved physical properties generating a ‘low’ compounding / unit cost. The increase in the density cost factor is offset to other mineral reinforcements due to a lower loading level typically achieving a better balance of properties. Wollastonite is priced comparably to other mineral reinforcements and much lower than glass fibre. Depending on the Engineering Standard for a composite, NYCO’s high aspect ratio grades have been found to be able to totally replace short milled glass and as an extension to chopped glass. This in turn provides a considerable improvement in surface appearance for both unpainted and painted applications.