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Prepare composite materials with recycled fibers from waste newspaper and PLA by inject-molding process, and study on recycled fiber of the modified-property treatment of silane coupling agent and alkali deinking treatment influence properties of composite materials. It is found out that, recycled fibers under the modified-property treatment of silane coupling agent and under alkali deinking treatment can effectively improve compatibility between recycled fibers and PLA, and improve mechanical properties and water absorbency of composite materials.

In order to make full use of old newspapers and preserve precious plant resource, old newspapers were reclaimed and refined into fiber, then phthalic anhydride (PA) was utilized to modify the reclaimed-fiber on the condition of ultrasonic radiation. Subsequently, reclaimed-fiber was mixed with polylactic acids (PLA) to obtain composites by means of extrusion molding. At last, mechanical performances of the composite were tested. Results reveal that: composite made form PLA and the PA treated reclaimed-fiber from old newspapers has good mechanical performances, and its tensile strength is higher than 41.5MPa while impact strength is no less than 7.3KJ/m2. Moreover, the optimum processing conditions for modifying reclaimed-fiber with PA are: mass fraction of phthalic anhydride to old newspaper reclaimed fiber 5%, ultrasonic radiation time 15min, and modification temperature 90°C.

Wood is one kind of renewable natural eco-material. Glued laminated timber (glulam) is an engineered wood product made from sawn lumber lamina glued together in horizontal layers. The application of glulam in the construction structure not only has great environmental value, but also reduces energy consumption and carbon emission of the construction. In this study, we evaluated the effects of different factors on the structural properties of glulam and designed several enhancement modes to reinforce the glulam with FRP (Fiber Reinforced Plastic). Then, we measured the mechanical properties of the glulam specimens in the different enhancement modes and selected the optimal reinforcement mode. The reinforcement method obviously increased the value of MOE and MOR of poplar glulam by 5%-15% and 5%-12% respectively. FRP length of 600mm was the optimal and most economic reinforcement length, and finger joint position of 300mm is the optimal position.