The role of fiberglass in reinforced plastics composite has been experimentally investigated. Polypropylene composites filled with fiberglass of two forms were used for the studies. The results indicated that the tensile strength of polypropylene composite filled with continuous fiberglass was almost 85% of the theoretically predicated strength values, and those filled with discontinuous fiberglass showed one half of them. When the surface of discontinuous fiberglass was pretreated by aminofunctional silane and methylvinyldichlorosilane, we obtained high strength.

이성분계 복합재료로서 Polypropylene-fiberglass의 복합소재를 가지고 Hollister의 이론을 실험적으로 밝히고 이론치와 비교했다. discontinuous fiber로 복합되었을 때는 그 강도가 이론치에 50%정도이고 continuous fiber의 경우는 85%정도임을 보여준다. 한편 여러가지 coupling agent 가운데 aminofunctional silane과 methyl vinyl dichlorosilane으로 함께 처리했을 때 강도가 뛰어난 복합 polypropylene을 얻었다.