RESPONSE-SURFACE METHODOLOGY - A USEFUL TOOL FOR THE OPTIMIZATION OF MOLECULAR ADHESION AND MECHANICAL-PROPERTIES OF PP COMPOSITES

Response surface design has been used to optimize the concentration of adhesion promoter in wood fiber-filled polypropylene composite in rel ation to maximization of mechanical properties and thermal stability o f modified composites. The method has also been used to find an empiri cal correlation between product composition and intermolecular bonding that has taken place due to the reactivity of itaconic anhydride modi fied polypropylene in the composite system studied. The adequency of t he correlation is further justified by FTIR and DSC results. The heat of fusion data of polypropylene in composite which was used as a relat ive measure of change in degree of crystallinity in polypropylene matr ix, fairly explains the observed effects of response variables on degr ee of chemical bonding and mechanical properties. The controlled varia bles selected in designing the experiment, however, suggests that a fu rther study is needed in the higher concentration range of wood fiber and modifier to optimize the cost and performance of product. Results in this study also revealed that a ridge analysis should be performed to find an unique extreme in the experimental region which will show t he direction to proceed to find the optimum in further experimentation . Overall, this study demonstrated that response surface methodology c ould be used to find a quantitative correlation between composite comp osition and mechano-chemical properties.