Application of the modified hybrid rule of mixture (ROHM) and Halpin– Tsai equation for predicting mechanical properties of wood/hemp/polymer composites

2019 ◽  
Vol 106 ◽  
pp. 4-8
Author(s):  
CEZARY GOZDECKI

Application of the modified hybrid rule of mixture (ROHM) and Halpin–Tsai equation for predicting mechanical properties of wood/hemp/polymer composites. An object of investigations was hybrid wood-polymer composite containing HDPE, hemp fibers and wood particles. The degree of addition of hemp and wood particles ranged from 0 to 60% of filler. The usefulness of the mathematical models ROHM and Halpin-Tsai to predict the Young's modulus of composites was tested. Additionally, experimental research was carried out. It was found that the hemp content in the wood-polymer composite significantly influences the growth of the composite module. The usefulness of mathematical models for predicting the Young's modulus of hybrid composites was also confirmed.

2011 ◽  
Vol 264-265 ◽  
pp. 819-824 ◽  
Author(s):  
Md. Rezaur Rahman ◽  
Sinin Hamdan ◽  
M. Saiful Islam ◽  
Md. Shahjahan Mondol

In Malaysia, especially Borneo Island Sarawak has a large scale of tropical wood species. In this study, selected raw tropical wood species namely Artocarpus Elasticus, Artocarpus Rigidus, Xylopia Spp, Koompassia Malaccensis and Eugenia Spp were chemically treated with sodium meta periodate to convert them into wood polymer composites. Manufactured wood polymer composites were characterized using mechanical testing (modulus of elasticity (MOE), modulus of rupture (MOR), static Young’s modulus) and decay resistance test. Modulus of elasticity and modulus of rupture were calculated using three point bending test. Static Young’s modulus and decay resistance were calculated using compression parallel to gain test and natural laboratory decay test respectively. The manufactured wood polymer composites yielded higher modulus of elasticity, modulus of rupture and static Young’s modulus. Wood polymer composite had high resistant to decay exposure, while Eugenia Spp wood polymer composite had highly resistant compared to the other ones.


2010 ◽  
Vol 34-35 ◽  
pp. 1165-1169 ◽  
Author(s):  
Yong Feng Li ◽  
Bao Gang Wang ◽  
Qi Liang Fu ◽  
Yi Xing Liu ◽  
Xiao Ying Dong

In order to improve the value-added applications of low-quality wood, a novel composite, wood-polymer composite, was fabricated by in-situ terpolymerization of MMA, VAc and St within wood porous structure. The structure of the composite and the reaction of monomers within wood were both analyzed by SEM and FTIR, and the mechanical properties were also evaluated. The SEM observation showed that the polymer mainly filled up wood pores, suggesting good polymerizating crafts. The FTIR results indicated that under the employed crafts, three monomers terpolymerized in wood porous structure, and grafted onto wood matrix through reaction of ester group from monomers and hydroxyl group from wood components, suggesting chemical combination between the two phases. The mechanical properties of the wood-polymer composite involving modulus of rupture, compressive strength, wearability and hardness were improved 69%, 68%, 36% and 210% over those of untreated wood, respectively. Such method seems to be an effective way to converting low-quality wood to high-quality wood.


BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 5141-5155
Author(s):  
Piotr Borysiuk ◽  
Jacek Wikowski ◽  
Krzysztof Krajewski ◽  
Radosław Auriga ◽  
Adrian Skomorucha ◽  
...  

This study investigated the possibility of applying flat-pressed wood-polymer composites in conditions of high humidity. The experiment involved three variants of wood-polymer composite panels 16 mm thick, and 680 kg per m3 density. The wood particles were bonded with polyethylene. The share of polyethylene in the core layer was fixed at 50%, while in the face layers the content was varied (40%, 50%, or 60%). The following parameters were examined: modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), screw holding (SH), thickness swelling (TS), water absorption (WA), susceptibility to drilling and milling, wettability and surface free energy, and resistance to mold. The results were compared to particleboard glued with urea-formaldehyde resin. The wood-polymer composite had lower MOR and MOE values and similar IB and SH values. The panels indicated a remarkably higher water resistance (lower TS and WA values) with good surface wettability and high resistance to mold fungi. Additionally, the composites were easier to machine, e.g. drilling or milling, in comparison to standard particleboards.


2021 ◽  
Vol 410 ◽  
pp. 593-598
Author(s):  
Anton M. Kuzmin ◽  
Nadir Ayrilmis ◽  
Vladimir N. Vodyakov

This paper is devoted to the study of the technological process for the production of tape from polyethylene and wood-polymer composite by extrusion. At the first stage, the wood-polymer composite granulate was obtained on a co-rotating twin-screw extruder. The tape was made on a Rheomex 19/25 PolyLab OS single-screw extruder with a barrel length L/D = 25. The processing temperature of the wood-polymer composite was in the range of 145 ... 160°C. The tensile strength and elasticity modulus in tension, water absorption per day and density were investigated for the developed wood-polymer composite and polyethylene. It has been found out that for the developed wood-polymer composite, the strength and elastic modulus along the stretch direction increase by 11% and 6%, respectively. Orientation stretching has a significant effect on the physical and mechanical properties of wood-polymer composites.


2013 ◽  
Vol 34 (10) ◽  
pp. 1567-1574 ◽  
Author(s):  
Jianchen Cai ◽  
Mingyin Jia ◽  
Ping Xue ◽  
Yun Ding ◽  
Xiang Zhou

Author(s):  
W Wang ◽  
P Ciselli ◽  
E Kuznetsov ◽  
T Peijs ◽  
A.H Barber

Carbon nanotubes have mechanical properties that are far in excess of conventional fibrous materials used in engineering polymer composites. Effective reinforcement of polymers using carbon nanotubes is difficult due to poor dispersion and alignment of the nanotubes along the same axis as the applied force during composite loading. This paper reviews the mechanical properties of carbon nanotubes and their polymer composites to highlight how many previously prepared composites do not effectively use the excellent mechanical behaviour of the reinforcement. Nanomechanical tests using atomic force microscopy are carried out on simple uniaxially aligned carbon nanotube-reinforced polyvinyl alcohol (PVA) fibres prepared using electrospinning processes. Dispersion of the carbon nanotubes within the polymer is achieved using a surfactant. Young's modulus of these simple composites is shown to approach theoretically predicted values, indicating that the carbon nanotubes are effective reinforcements. However, the use of dispersant is also shown to lower Young's modulus of the electrospun PVA fibres.


2009 ◽  
Vol 79-82 ◽  
pp. 1527-1530
Author(s):  
Yong Feng Li ◽  
Yi Xing Liu ◽  
Hai Peng Yu ◽  
Wen Shuai Chen

Wood as a porous structure has weak durability and unsatisfactory mechanical properties which limits its utilization. For this reason, the study presents a two-step method to prepare a new modified wood material—Wood Polymer Composite. Maleic anhydride(Man) firstly penetrates into the porous structure of wood, followed by a reaction with wood cell walls. Then, Styrene(St) with some Man and a few amount of initiator, AIBN, permeate through the whole wood and react with the above modified wood. The structural characterization of wood polymer composite with SEM and FTIR indicates that Man reacts successfully with the hydroxyl group of wood cell wall by its anhydride group, and further reacts fully with styrene as a free radical copolymerization form by its double bond; and thus the polymer fills in wood cell lumina as a solid form, which combines the wood cell walls without any evident crack. The testing results of properties show that the mechanical properties of wood polymer composite increase by about 50%-250% over those of unmodified wood, and its durability improve 1.9-4.89 times than untreated wood.


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