High Temperature Compounds
RTP Company offe
RTP Company offers reinforced, non-reinforced and precolored high temperature compounds. In many cases, high temperature compounds are specified for applications that require enhanced wear properties.
High temperature materials are divided into two main categories based on their difference in molecular structure: semi-crystalline and amorphous.
Semi-Crystalline Materials
Semi-crystalline materials have a highly ordered molecular structure with sharp melt points. Much like an ice cube, they remain solid until a given quantity of heat is absorbed, then rapidly change into a low viscosity liquid.
These materials are anistropic in flow - shrinking less in the direction of flow versus transverse to flow. They have excellent chemical resistance.
Semi-crystallines exhibit substantial improvement in their HDTs when reinforced. They retain useful values and have load bearing capabilities well above their glass transition temperature (Tg).
Amorphous Materials
Amorphous high temperature resins have a randomly ordered molecular structure which reacts like molasses -- softening gradually as the temperature rises. These materials change viscosity when heated, but seldom are as easy flowing as semi-crystalline materials.
They are isotropic in flow - shrinking uniformly in the direction of flow and transverse to flow. As a result, amorphous materials typically exhibit lower mold shrinkage and less tendency to warp than the semi-crystalline materials.
Amorphous resins lose their strength quickly above their glass transition temperature (Tg).
Selecting the right high temprature compound requires consideration of several key measurements, including heat deflection temperature (HDT), continuous use temperature or property retention, and elevated temperature physical properties.
RTP Company, 580 East Front Street, P.O. Box 439. Tel: 507-454-6900; Fax: 507-454-2041.