Elastomer coated fillers and composites thereof comprising at least 60% by wt. of a hydrated filler and an elastomer containing an acid substituent

US4373039A · kind A · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• William A. Mueller · Glendale, US
• John D. Ingham · La Cañada Flintridge, US
• William W. Reilly · Altadena, US

Key dates

• Filing date: Jun 11, 1980
• Grant date: Feb 8, 1983
• Expiry date: Jun 11, 2000

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08K3/22
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The impact resistance of flame retardant composites, especially thermoplastic molding compounds containing over 60% hydrated mineral filler such as Al(OH).sub.3 or Mg(OH).sub.2 is improved by coating the filler with 1 to 20% of an elastomer. The composite will fail by crazing or shearing rather than by brittle fracture. A well bonded elastomeric interphase results by utilizing acidic substituted resins such as ethyl-hexyl acrylate-acrylic acid copolymers which bond to and are cross-linked by the basic filler particles. Further improvement in impact resistance is provided by incorporating 1 to 10% of a resin fiber reinforcement such as polyvinyl alcohol fibers that decompose to yield at least 30% water when heated to decomposition temperature.