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Wood polymer composite is an important material class for industries. Microbiological properties can be an important aspect to enlarge its application base. The biocidal properties of wood polymer composite (WPC) can be aggregated by incorporation of biocidal additives on its composition. But, an important aspect is the evaluation the influence of the fabrication process on its biocidal properties. In particular, the temperature and screw velocity are important parameters for extrusion processes, and the mass proportions of the compounds are important factors to define the WPC properties. Different combinations of process conditions and mass proportions of the composite can promote variation in the magnitude of the bactericidal effect. The bactericidal properties are aggregated in the composite by organic bactericidal additive and the high temperature and high shear rate during the extrusion process can affect the effectiveness of the bactericidal additive function. This paper investigates the effects of the extrusion process parameters associated with different percentages of bactericidal additives on the WPC. The results showed significant effects on the bactericidal properties that depended only on the bactericidal content.

This work presents preliminary results of powder glasses with bactericide effect obtained by ionic exchange between sodium ions, present in glass composition, and silver ions, present in the ionic exchange medium. The powder glass was submitted to ionic exchange in ionic medium containing different concentration of silver species. The results showed a bactericide effect dependence on AgNO3 concentration in the ionic medium. Agar Diffusion Test on Escherichia coli bacteria, EDS analyses was applied to the samples; the results showed there is a critical concentration of silver ions incorporated in the powder glass and a limit to bactericide effect. The tests and analyses reveled that 6 wt% of AgNO3 in ionic medium was the critical concentration.

These work present studies about influence of the high temperature at the antimicrobial properties of the Bactericide Wood Polymer Composites (BWPC) after exposition during different times at 110 oC. The composite was formulated containing Polypropylene (PP) as matrix polymeric, wood powder of the species Pinus and Triclosan additive as bactericide agent. The BWPC was exposited during different times in the ambient and submitted to microbiological tests. The Agar Diffusion tests were applied with two kind bacteria, the Echerichia coli (EC - Gram Positive) and Staphylococcus aureos (SA - Gram Negative). The FT-IR and TGA techniques were utilized to available of the temperature effect in the chemical structure of the composites BWPC. The studies showed a strong dependence of the bactericide action of the composites with exposition time at 110 oC and a constant bactericide action after 100 hours of exposition.