Flour rice husk as filler in block copolymer polypropylene: Effect of different coupling agents

• Published in: Journal of applied polymer science Vol. 99; no. 4; pp. 1823 - 1831
• Main Authors: Martí-Ferrer, Ferran, Vilaplana, Francisco, Ribes-Greus, Amparo, Benedito-Borrás, Adolfo, Sanz-Box, Concha
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15-02-2006; Wiley
• Subjects: Applied sciences; compatibilization; Composites; Exact sciences and technology; flour rice husk; Forms of application and semi-finished materials; natural fiber composites; Polymer industry, paints, wood; polypropylene; Technology of polymers; viscoelastic properties; Viscoelasticity; Propylene copolymer; Olefin copolymer; compatibilization; Dispersion reinforced material; polypropylene; Property processing relationship; Composite material; Impact strength; Agricultural waste; flour rice husk; Mechanical properties; Organic silane; Titanates; Organic anhydride; Experimental study; Rice by product; Functional polymer; Surface treatment; viscoelastic properties; Coupling agent; Polymer filler interaction; Dynamic mechanical properties; natural fiber composites; Block copolymer; Rheological properties
• ISSN: 0021-8995; 1097-4628; 1097-4628
• DOI: 10.1002/app.22717

Flour rice husk (FRH) was employed as a filler in block copolymer polypropylene (PPB) in order to prepare polymer‐based reinforced composites. Four coupling agents were selected to modify the surface of the rice husk in the composite materials, including two types of functionalized polymers [PP homopolymer grafted with maleic anhydride (MA‐PP) and an elastomer styrene–ethylene–butadiene–styrene triblock copolymer grafted with MA (MA‐SEBS)] and two bifunctional organometallic coupling agents (silane and titanate with linear low‐density polyethylene as a carrier). The influence of each type of coupling agent on the interfacial bonding strength was studied by dynamic mechanical analysis, scanning electronic microscopy, and rheological tests. The results showed that strong interactions were formed between the coupling agents and the filler surface. The addition of a coupling agent with an elastomeric carrier (MA‐SEBS) increased the loss tangent and reduced the storage modulus of the composite. A similar but less intense effect was observed for the titanate coupling agent. However, an antagonistic performance was obtained when MA‐PP and silane were employed as coupling agents. In addition, when the percentage of MA‐SEBS was increased, the impact properties of FRH/PPB blends were improved and the strength was reduced. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1823–1831, 2006