Home  About us  Contact
 

Wood Composites (wood + composite)

Distribution by Scientific Domains
Polymers and Materials Science75%

Selected Abstracts

Development of poly(vinyl chloride)/wood composites.

JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 2 2004
A literature review
Poly(vinyl chloride)/wood fiber (flour) composites are currently experiencing a dramatic increase in use. Most of them are used to produce window/door profiles, decking, railing, and siding by using conical counterrotating intermeshing twin-screw extruders. Heat stabilizers, processing aids, impact modifiers, lubricants, and pigments are still important for PVC/wood composite formulations. Poly[methylene(polyphenyl isocyanate)] (PMPPIC), ,-aminopropyltriethoxysilane, maleated polypropylene (MAPP), and copper metallic complex have proved to be effective coupling agents for this composite system. Mechanical properties of PVC/wood composites can be enhanced by combining wood with mica or glass fibers to form hybrid reinforcements. Ultraviolet light resistance and weathering dimensional stabilities of PVC/wood composites are superior to those of natural wood. Density reduction can be achieved through the microcellular foaming technique by using chemical blowing agents, such as azodicarbonamide and sodium bicarbonate, or physical blowing agents, such as carbon dioxide. J. Vinyl Addit. Technol. 10:59,69, 2004. © 2004 Society of Plastics Engineers. [source]

Dynamic mechanical properties of extruded nylon,wood composites

POLYMER COMPOSITES, Issue 4 2008
Jianmin Chen
Dynamic mechanical properties determine the potential end use of a newly developed extruded nylon,wood composite in under-the-hood automobile applications. In this article, the dynamic mechanical properties of extruded nylon,wood composites were characterized using a dynamic mechanical thermal analyzer (DMTA) to determine storage modulus, glass transition temperature (Tg), physical aging effects, long-term performance prediction, and comparisons to similar products. The storage modulus of the nylon,wood composite was found to be more temperature stable than pure nylon 66. The Tg range of the nylon,wood composite was found to be between 23 and 56°C, based on the decrease in storage modulus. A master curve was constructed based on the creep curves at various temperatures from 30 to 80°C. The results show that the relationship between shift factors and temperature follows Arrhenius behavior. Nylon,wood composites have good temperature-dependent properties. Wood fillers reduced the physical aging effects on nylon in the wood composites. The comparison of the nylon,wood composite with other similar products shows that nylon,wood composites are a promising low cost material for industrial applications. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers [source]

An experimental study of single-screw extrusion of HDPE,wood composites

ADVANCES IN POLYMER TECHNOLOGY, Issue 3 2010
Karen Xiao
Abstract Single-screw extrusion experiments were carried out to study the extrusion characteristics of HDPE,wood composites. Three screw geometries (A, B, and C) were used, and the effects of screw speed on output, melting, and pressure profile were studied. Screw A had a much higher compression ratio than screws B and C, which directly affected the melting behavior of the polymers. Screws B and C had the same compression ratio; however, screw C had the same metering capacity as screw A. Therefore, by comparing screws B and C, the effect of feed depth on the solid conveying capacity was investigated. It was found that while screw B had higher outputs than both screws A and C as expected, screw C had a much lower output than screw A for highly filled resins even though they had the same metering capacity. For HDPE, screws A and C showed the same output as expected. Further examinations of the pressure profiles and melting profiles from screw extraction experiments confirmed that screw C showed a severely starved solids conveying capacity for wood-filled resins, which limited the total outputs. Comparing the outputs and pressure generations between theoretical predictions and actual experimental results, it was evident that due to the inaccurate assumption of fully filled channels common in single screw extrusion, both outputs and pressure generations in the extruders were overpredicted. © 2010 Wiley Periodicals, Inc. Adv Polym Techn 29:197,218, 2010; View this article online at wileyonlinelibrary. DOI 10.1002/adv.20190 [source]

Dynamic mechanical properties of extruded nylon,wood composites

POLYMER COMPOSITES, Issue 4 2008
Jianmin Chen
Dynamic mechanical properties determine the potential end use of a newly developed extruded nylon,wood composite in under-the-hood automobile applications. In this article, the dynamic mechanical properties of extruded nylon,wood composites were characterized using a dynamic mechanical thermal analyzer (DMTA) to determine storage modulus, glass transition temperature (Tg), physical aging effects, long-term performance prediction, and comparisons to similar products. The storage modulus of the nylon,wood composite was found to be more temperature stable than pure nylon 66. The Tg range of the nylon,wood composite was found to be between 23 and 56°C, based on the decrease in storage modulus. A master curve was constructed based on the creep curves at various temperatures from 30 to 80°C. The results show that the relationship between shift factors and temperature follows Arrhenius behavior. Nylon,wood composites have good temperature-dependent properties. Wood fillers reduced the physical aging effects on nylon in the wood composites. The comparison of the nylon,wood composite with other similar products shows that nylon,wood composites are a promising low cost material for industrial applications. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers [source]

Interfacial adhesion and molecular diffusion in melt lamination of wood sawdust/ebonite NR and EPDM

POLYMER COMPOSITES, Issue 3 2009
W. Yamsaengsung
Adhesion mechanisms and peel strengths of wood/ebonite NR-EPDM laminates were investigated. Three different chemical coupling agents: namely; N-(, aminoethyl)-,-aminopropyl-triethoxysilane (AAS), 3-methacryloxypropyl trimethoxysilane (ACS), and Bis-(3-triethoxylpropyl) tetrasulfan (Si69) were introduced into the wood/NR composites to enhance an interaction between wood sawdust (SD) particles and NR molecules, and to improve the adhesion strength between the SD/NR and EPDM layers. The quantitative evidences were given to explain the changes in the adhesion or peel strengths of the SD/NR-EPDM laminates through scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDS). The experimental results indicated that the suitable cure time and cure temperature for SD/NR-EPDM melt-laminates were the tc90 of SD/NR composites and 140°C, respectively. The Si69 coupling agent was found to be the most effective coupling agent as compared with AAS and ACS coupling agents. The Si69 of 0.5 wt% was recommended for the optimizations of the tensile modulus of the SD/NR composites and the peel strength of the SD/NR-EPDM laminates. The diffusion level between the SD/NR and EPDM layers could be quantitatively substantiated by determining the sulfur content transfer from the SD/NR layer to the EPDM layer. The diffusion and entanglement of molecular chains from the SD/NR to the EPDM layer initiated the co-crosslinking reaction which played an important role on the changes in the interfacial strength in the SD/NR-EPDM melt-laminates. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers [source]