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Sisal fiber (SF)‐reinforced poly(lactic acid) (PLA) biocomposites were prepared from biodegradable PLA and surface‐untreated or ‐treated short SF by melt mixing and subsequent compression molding. It is found that the surface treatments facilitate good adhesion between SFs and PLA matrix, which is consistent with the higher mechanical properties of the treated‐SF/PLA biocomposites. Moreover, the surface treatments have similar effects on the biodegradability and water absorption of the biocomposites with the order as following: neat PLA < acetylated SF (A‐SF)/PLA biocomposite ≈ silane‐treated SF (S‐SF)/PLA biocomposite < permanganate‐treated SF (P‐SF)/PLA biocomposite < mercerized SF (M‐SF)/PLA biocomposite < untreated fiber (U‐SF)/PLA biocomposite. In terms of overall consideration of the properties, acetylation treatment seems to be the most desirable surface method owing to the maximum tensile strength and water resistance, medium impact strength, and minimum degradability of the A‐SF/PLA biocomposite. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers

Chelating resins are useful substances in industry because of their extraordinary adsorption properties for specific metal ions. In this study, a new type of chelating resin is synthesized simply by reaction between thiourea and formaldehyde. The synthetic conditions and the structure of the product are approached and the adsorbing capacities for 11 metal ions, adsorbing rates, and selectivities investigated. The results of the experiments show that the resin has high adsorbing capacities for Ag(I): 13.1 mmol/g, and for Au(III): 6.95 mmol/g. Adsorbing rates are close to 100% in dilute solution. Isothermal adsorbing study reveals that the adsorption is monomolecular layer adsorption process. It is hopeful for the resin to be used for concentrating and retrieving Ag(I) and Au(III) ions from their dilute solutions in industry.