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Tensile strength and shear strength parallel to the grain of poplar (a, c) and radiata pine (b, d) untreated and treated with 10% SAC and varying concentrations of SS, respectively. The labels in the x-coordinate and the meaning of box chart are same as Fig. 2

Tensile strength and shear strength parallel to the grain of poplar (a, c) and radiata pine (b, d) untreated and treated with 10% SAC and varying concentrations of SS, respectively. The labels in the x-coordinate and the meaning of box chart are same as Fig. 2

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Poplar (Populus adenopoda Maxim.) and radiata pine (Pinus radiata Don.) woods were treated with an aqueous solution containing styrene-acrylic copolymer (SAC) dispersion and sodium silicate (SS). The modifying effects on the mechanical properties of wood were investigated with 10% SAC and varying concentrations of SS. The SAC and the SS deposition...

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... tensile strength and shear strength parallel to the grain of the treated and untreated wood specimens are presented in Fig. 6. These results revealed that treat- ment of the wood with SAC resulted in an improve- ment in both the tensile strength and shear ...
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... strengths also increased drastically when SS was added due to the reinforcement effect of the SAC- SS inclusions in the cell lumina, which was similar to its bending behavior. At the highest SS concentration (15%), the tensile strength of the modified poplar and radiata pine wood specimens was increased by about 38.4 and 38.3%, respectively (Fig. 6a, b), while their shear strength was increased by about 53.1 and 41.4%, respectively (Fig. 6c, ...
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... of the SAC- SS inclusions in the cell lumina, which was similar to its bending behavior. At the highest SS concentration (15%), the tensile strength of the modified poplar and radiata pine wood specimens was increased by about 38.4 and 38.3%, respectively (Fig. 6a, b), while their shear strength was increased by about 53.1 and 41.4%, respectively (Fig. 6c, ...
Context 4
... tensile strength and shear strength parallel to the grain of the treated and untreated wood specimens are presented in Fig. 6. These results revealed that treat- ment of the wood with SAC resulted in an improve- ment in both the tensile strength and shear ...
Context 5
... strengths also increased drastically when SS was added due to the reinforcement effect of the SAC- SS inclusions in the cell lumina, which was similar to its bending behavior. At the highest SS concentration (15%), the tensile strength of the modified poplar and radiata pine wood specimens was increased by about 38.4 and 38.3%, respectively (Fig. 6a, b), while their shear strength was increased by about 53.1 and 41.4%, respectively (Fig. 6c, ...
Context 6
... of the SAC- SS inclusions in the cell lumina, which was similar to its bending behavior. At the highest SS concentration (15%), the tensile strength of the modified poplar and radiata pine wood specimens was increased by about 38.4 and 38.3%, respectively (Fig. 6a, b), while their shear strength was increased by about 53.1 and 41.4%, respectively (Fig. 6c, ...

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... Yan et al. (2015) compounded glyoxal, urea and nano-SiO 2 to prepare glyoxal-urea/nano-SiO 2 composite modifier, and used the impregnation method to combine the composite modifier with poplar wood to enhance the mechanical properties and flame retardant properties of fastgrowing wood. Nguyen et al. (2019) used styrene-acrylic acid copolymer dispersion and sodium silicate to modify poplar wood, and the flexural strength, compressive strength, surface hardness, and shear strength of the modified wood were improved by 83.9%, 82.3%, 72.7%, and 38.4%, respectively. Wu et al. (2021) used graphene/polyvinyl alcohol (Gr/PVA) impregnated mixture to modify poplar wood, and the crystallinity of the modified wood was reduced but the thermal stability was improved. ...
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... Therefore, the development of an environmentally friendly resin system for impregnating and filling the cell lumen is a breakthrough to solve the bottleneck problem of poplar. Waterbased acrylic resins [40][41][42][43][44][45][46][47], furfuryl alcohol resins [48][49][50][51], polyester resins [52][53][54] and 2D resins [55][56][57] have been studied as environmentally friendly filler modifiers to replace aldehyde resins [58]. ...
... Most of all, acrylic resins exhibit good bending resistance [40][41][42][43][44][45], compressive properties [41][42][43], surface hardness [40,41,43] and dimensional stability [42,43], due to their relatively high molecular weight. However, two difficulties remain in these resins: (1) the resin needs to be fitted with a suitable curing agent to fill the cell cavity firmly, and matching the correct curing agent is a difficult task; (2) although the high molecular weight of the resin is beneficial to wood modification, it tends to lead to the high viscosity of the resin liquid, especially for large-size solid wood, which is difficult to penetrate and fill evenly. ...
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In order to improve the performance of soft plantation wood, an environmentally friendly inorganic-organic hybrid wood modifier was developed. First, using urea and melamine as crosslinking agents, the waterborne glucose silicone resin (MUG) was prepared with glucose under the catalysis of inorganic acid and metal ions. Then MUG resin was diluted to 10% and 20% mass fraction, and compounded with sodium silicate (S) of 20% and 10% mass fraction, so the inorganic-organic hybrid G10S20 and G20S10 wood modifier were obtained respectively. Then plantation poplar wood (Populus tomentosa) were impregnated and modified with them. Their physical and mechanical properties were tested and compared with those of the wood treated with S of 20% mass fraction (S20). Infrared analysis showed that amino resin characteristic structure (CO-NH-) existed in MUG resin. The resin has good permeability. Compared with S20 modified wood, the degree of shrinkage of G10S20 or G20S10 modified wood is reduced, their moisture absorption is reduced, and their dimensional stability is improved. Waterborne glucose silicone modifier can effectively improve the wood density, modulus of elasticity, modulus of rapture and compression strength. SEM analysis showed that the cell wall of G20S10 modified wood was significantly thicker than the untreated wood, and there were columnar and granular solid substances attached in some cell cavities, ducts and corners, etc. EDX showed that the number of Si elements on the cell wall was significantly increased compared with the control, indicating that the modifier effectively entered the wood cell wall. The waterborne glucose silicone resin can greatly improve the physical and mechanical properties of wood through organic-inorganic hybridization. It is a green, non-formaldehyde, eco-friendly, low cost, compound wood modifier with broad application prospects.
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