Effect of fiber pretreatment condition on the interfacial strength and mechanical properties of wood fiber/PP composites

Abstract

ABSTRACT:The effect of fiber surface pretreatment on the interfacial strength and mechanical properties of wood fiber/polypropylene (WF/PP) composites are investigated. The results demonstrate that fiber surface conditions significantly influence the fiber-matrix interfacial bond, which, in turn, determines the mechanical properties of the composites. The WF/PP composite containing fibers pretreated with an acid-silane aqueous solution exhibits the highest tensile properties among the materials studied. This observation is a direct result of the strong interfacial bond caused by the acid/ water condition used in the fiber pretreatment. Evidence from coupling chemistry, rheological and electron microscopic studies support the above conclusion. When SEBSg-MA copolymer is used, a synergistic toughening effect between the wood fiber and the copolymer is observed. The V-notch Charpy impact strength of the WF/PP/SEBS-g-MA composite is substantially higher than that of the WF/PP composite. The synergistic toughening mechanisms are discussed with respect to the interfacial bond strength, fiber-matrix debonding, and matrix plastic deformation.

Tensile Behaviour and Morphology of Polypropylene/Polycar-bonate/Polypropylene-graft-maleic Anhydride Blends

“…It is suspected that there is a little adhesion bond presence when PP-g-MA is used, based on the tensile strength result. Tensile tests can roughly estimate the interfacial adhesion strength between matrix and reinforcement phases of the PP/PC immiscible blends, as a good tensile strength reflects a strong interfacial adhesion [13]. …”

“…The improvement was particularly obvious at 50/30/20 composition, and was attributed to interfacial agent role by PP-g-GMA. Tensile strength is the direct indication of the interfacial adhesion in polymer composites [13]. A good tensile strength reflects a strong interfacial adhesion.…”

Compósitos termoplásticos com madeira

“…Considerações sobre processo, compatibilização e propriedades têm sido abordadas por inúmeros autores [10][11][12][13][14][15][16][17] . Esse amplo interesse baseia-se no fato de que a incorporação de fibras naturais em termoplásticos poliolefínicos apolares, o caráter polar da celulose requer a compatibilização do sistema através da incorporação dos chamados agentes de acoplamento ou de adesão interfacial.…”

“…Outro aspecto considerado é o comprimento das cadeias do compatibilizante que deve possuir cadeias suficientemente longas de alta massa molecular que permita a formação de emaranhamentos moleculares com a matriz polimérica na interfase através de ancoramento mecânico. Alguns autores relacionam o tratamento superficial da fibra como forma de optimização do processo de compatibilização [15][16][17][18][19][20] .…”

Direct Numerical Simulation of Fracture Behaviour for Random Short Wood Fibres Reinforced Composites, Comparison with Digital Image Correlation Experiments

“…In order to be able to meet the high demands on stiffness and strength, polypropylene must often be reinforced. A variety of natural fibres are available for reinforcement in polypropylene, for example: flax, hemp, sisal, bamboo [3]. In the present study, spruce fibres (sawdust) have been incorporated successfully into polypropylene with different fibre weight fractions in order to produce the spruce fibres/PP composite [4].…”