Reactive maleic anhydride polyolefins (MAPOs) in oriented strand board. Part 1: Dynamic thermomechanical properties of phenol formaldehyde resins blended with two MAPOs

Holzforschung ◽  
2011 ◽  
Vol 65 (1) ◽  
pp. 81-87 ◽  
Author(s):  
Sudip Chowdhury ◽  
Vikram Yadama ◽  
Marie-Pierre Laborie
Keyword(s):  
Phase Separation ◽  
Maleic Anhydride ◽  
Moisture Content ◽  
Oriented Strand Board ◽  
Phenol Formaldehyde ◽  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Resin System ◽  
Wood Composites ◽  
Low Levels

Abstract A mechanism to improve the toughness of phenol formaldehyde (PF) resin for wood composites is investigated. It is hypothesized that addition of maleic anhydride polyolefins (MAPO), namely maleic anhydride polypropylene (MAPP) and maleic anhydride polyethylene (MAPE), to PF resin will toughen it owing to phase separation between the resin and MAPO. Dynamic mechanical analysis of resin with a low level of MAPP (0.5%) showed an improvement in the storage modulus (E′) or stiffness of the resin system during curing. Similarly, the damping property, tanδ, examined at three discrete temperatures, improved with blends of low levels of MAPP (0.5%). The fracture energies (GIc and GIa) at 12% moisture content were increased with the addition of MAPP at lower proportions (1.5%, 3%, and 4.5%); whereas the addition of MAPE showed a reduction in fracture energies, although not significant, particularly at lower levels. After 24 h soaking, specimens with MAPP showed significant improvements in GIc only at the 3% level; however, addition of MAPE resulted in a reduction of both the fracture energies. On the basis of these results, PF resin was blended with MAPP anionic emulsion for fabrication of oriented strand composites (OSC) test boards in Part 2 of the study.

Reactive maleic anhydride polyolefins (MAPOs) in oriented strand board. Part 2: Influence on physical and mechanical properties

Holzforschung ◽  
2011 ◽  
Vol 65 (1) ◽  
pp. 89-96 ◽  
Author(s):  
Sudip Chowdhury ◽  
Vikram Yadama
Keyword(s):  
Mechanical Properties ◽  
Maleic Anhydride ◽  
Oriented Strand Board ◽  
Phenol Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Modulus Of Rupture ◽  
Moisture Resistance ◽  
Thickness Swelling ◽  
Water Vapor Transmission ◽  
Reduced Water

Abstract The use of reactive polyolefin and phenol formaldehyde (PF) resin blends to improve the moisture durability of oriented strand composite (OSC) panels was investigated. Test panels were hot pressed with adhesive blends consisting of varying proportions of PF and maleic anhydride polypropylene (MAPP) anionic emulsion, and their physical and mechanical properties were evaluated. The addition of MAPP did not significantly affect the modulus of elasticity (MOE) of the panels, but reduced the modulus of rupture in bending (MOR) for 12% moisture content (MC) and 24-h soak specimens. An increase in PF content significantly improved the MOE and MOR of specimens subjected to the environment. Adding MAPP reduced internal bond strength, particularly at higher PF levels. The addition of MAPP and raising PF levels significantly reduced water absorption and thickness swelling of the panels. At higher MAPP levels, the water vapor transmission in OSC as well as the permeance of the material, was reduced. Composite board equilibrated to lower MC with increasing MAPP content in the resin blend. The results indicate that increasing the PF content is the most effective method of improving both moisture resistance and the mechanical properties of OSC; addition of MAPP improves the moisture resistance of the panels, but significantly reduces their mechanical properties.

Influence of filler hybridization on thermomechanical properties of hemp/silver epoxy composite

2020 ◽  
pp. 096739112097811
Author(s):  
Munjula Siva Kumar ◽  
Santosh Kumar ◽  
Krushna Gouda ◽  
Sumit Bhowmik
Keyword(s):  
Thermal Conductivity ◽  
Silver Nanoparticles ◽  
Epoxy Polymer ◽  
Hybrid Composites ◽  
Conductive Filler ◽  
Weight Fraction ◽  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Material Behavior ◽  
Good Crystallinity

The polymer composite material’s thermomechanical properties with fiber as reinforcement material have been widely studied in the last few decades. However, these fiber-based polymer composites exhibit problems such as fiber orientation, delamination, fiber defect along the length and bonding are the matter of serious concern in order to improve the thermomechanical properties and obtain isotropic material behavior. In the present investigation filler-based composite material is developed using natural hemp and high thermal conductive silver nanoparticles (SNP) and combination of dual fillers in neat epoxy polymer to investigate the synergetic influence. Among various organic natural fillers hemp filler depicts good crystallinity characteristics, so selected as a biocompatible filler along with SNP conductive filler. For enhancing their thermal conductivity and mechanical properties, hybridization of hemp filler along with silver nanoparticles are conducted. The composites samples are prepared with three different combinations such as sole SNP, sole hemp and hybrid (SNP and hemp) are prepared to understand their solo and hybrid combination. From results it is examined that, chemical treated hemp filler has to maximized its relative properties and showed, 40% weight % of silver nanoparticles composites have highest thermal conductivity 1.00 W/mK followed with hemp filler 0.55 W/mK and hybrid 0.76 W/mK composites at 7.5% of weight fraction and 47.5% of weight fraction respectively. The highest tensile strength is obtained for SNP composite 32.03 MPa and highest young’s modulus is obtained for hybrid composites. Dynamic mechanical analysis is conducted to find their respective storage modulus and glass transition temperature and that, the recorded maximum for SNP composites with 3.23 GPa and 90°C respectively. Scanning electron microscopy examinations clearly illustrated that formation of thermal conductivity chain is significant with nano and micro fillers incorporation.

A Study on the Blends of Epoxy/Polybutadiene and the Application to the Encapsulation of a Capacitor

1992 ◽  
Vol 274 ◽  
Author(s):  
Zhongyuan Ren ◽  
Liying Qui
Keyword(s):  
Phase Separation ◽  
Dynamic Mechanical Analysis ◽  
Low Temperatures ◽  
Epoxy Resins ◽  
Mechanical Analysis ◽  
Dynamic Mechanical

ABSTRACTThis paper describes the blends of epoxy/polybutadiene and the application of the blends to the encapsulation of capacitors. Experiments showed that the hydroxy-carboxyl terminated polybutadiene (HCTPB) had a good toughening effect on epoxy resins, and the blends of epoxy/HTPB or epoxy/HCTPB had good craze resistance at low temperatures. The phase separation and dynamic mechanical analysis of these blends are discussed below.

A strengthening approach for damping property and shape memory property of acrylic rubber/polylactide blends

2018 ◽  
Vol 51 (7-8) ◽  
pp. 626-643
Author(s):  
Chengliang Li ◽  
Xingxing Ji ◽  
Yang Lyu ◽  
Xinyan Shi
Keyword(s):  
Shape Memory ◽  
Loss Factor ◽  
Phenol Formaldehyde ◽  
Mechanical Analysis ◽  
Damping Properties ◽  
Shape Memory Property ◽  
Memory Property ◽  
Damping Material ◽  
Shape Memory Properties ◽  
Shape Memory Effects

In this work, a damping material was successfully prepared by blending acrylic rubber (ACM) and polylactide (PLA) with sulfur and soap salt as the curing agents. A phenol-formaldehyde (PF) resin was used as a modifier. The effects of PF on the mechanical properties, damping properties, compatibility and shape memory properties of the blends were studied. The compatibility and damping properties were characterized by dynamic mechanical analysis, Fourier transform infrared spectroscope and microstructure analysis. The shape memory properties were examined by thermal mechanical analyser. The results revealed that the tensile strength of the blends was decreased and the toughness was increased with the increase of PF loadings. The introduction of PF improved the compatibility between PLA and ACM, which was deduced from the fact that the glass transition temperature of ACM was increased and the two loss factor peaks became closer. It was also found that the loss factor peak became higher and the effective damping temperature range became wider due to the formation of hydrogen bonding, implying that the damping properties of ACM/PLA blends were significantly improved. The ACM/PLA blends exhibited good dual-shape memory effect and its shape recovery ratio was increased by introduction of PF and raising the trigger temperature. The blends also exhibited good triple-shape memory property, which was dramatically improved by the introduction of PF. The mechanisms for the enhanced shape memory effects were then analysed.

scholarly journals Influence of 1D and 2D Carbon Fillers and Their Functionalisation on Crystallisation and Thermomechanical Properties of Injection Moulded Nylon 6,6 Nanocomposites

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Fabiola Navarro-Pardo ◽  
Ana L. Martínez-Hernández ◽  
Victor M. Castaño ◽  
José L. Rivera-Armenta ◽  
Francisco J. Medellín-Rodríguez ◽  
...  
Keyword(s):  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Reduced Form ◽  
Scanning Calorimetry ◽  
Graphene Nanocomposites ◽  
Moulding Process ◽  
Nylon 6,6 ◽  
Injection Moulding Process ◽  
The One ◽  
Carbon Fillers

Carbon nanotubes (CNTs) and graphene were used as reinforcing fillers in nylon 6,6 in order to obtain nanocomposites by using an injection moulding process. The two differently structured nanofillers were used in their pristine or reduced form, after oxidation treatment and after amino functionalisation. Three low nanofiller contents were employed. Crystallisation behaviour and perfection of nylon 6,6 crystals were determined by differential scanning calorimetry and wide angle X-ray diffraction, respectively. Crystallinity was slightly enhanced in most samples as the content of the nanofillers was increased. The dimensionality of the materials was found to provide different interfaces and therefore different features in the nylon 6,6 crystal growth resulting in improved crystal perfection. Dynamical, mechanical analysis showed the maximum increases provided by the two nanostructures correspond to the addition of 0.1 wt.% amino functionalised CNTs, enhancing in 30% the storage modulus and the incorporation of 0.5 wt.% of graphene oxide caused an increase of 44% in this property. The latter also provided better thermal stability when compared to pure nylon 6,6 under inert conditions. The superior properties of graphene nanocomposites were attributed to the larger surface area of the two-dimensional graphene compared to the one-dimensional CNTs.

scholarly journals THE INFLUENCE OF SEVERAL TYPES OF RESINS ON THE DYNAMIC MECHANICAL PROPERTIES OF POLYMER MIXTURE BASED ON BUTYL RUBBER

2020 ◽  
Vol 3 (2) ◽  
pp. 36-45 ◽  
Author(s):  
O. Tarasova ◽  
Yu. Yurkin ◽  
A. Toroschin
Keyword(s):  
Phenol Formaldehyde ◽  
Dynamic Properties ◽  
Dynamic Mechanical Properties ◽  
Mechanical Analysis ◽  
Strength Properties ◽  
Butyl Rubber ◽  
Polymer Materials ◽  
Polymer Mixture ◽  
Damping Properties ◽  
Dynamic Mechanical

this work is devoted to the problem of developing vibration-damping polymer materials with high damping properties in a wide temperature range. The study of the effect of modifying additives on the strength, damping, adhesive and cohesive properties of a butyl rubber composite is the aim of this work. The task is to identify the actual temperature, frequency, dynamic and mechanical characteristics of a composite material based on butyl rubber depending on the type and concentration of resins. The key methods for studying this problem is the dynamic mechanical analysis method, aimed at obtaining information about changes in the dynamic properties of polymer materials (bond strength with metal when peeling samples of composites, determining the flow resistance of samples, determining the migration of plasticizer). Due to the established experimental dependences, it was found that the addition of resins (3% by weight) in the composition based on butyl rubber leads to an increase in the damping properties of composite materials, and an increase to (4.25% by weight) leads to their decrease. It was established that the obtained filled mixtures with a high damping peak and good adhesive and strength properties are mixtures with the addition of alkyl phenol-formaldehyde resins.

scholarly journals Performance of Oriented Strand Board Made with Soy Substituted Resin in Termite Choice Tests with Southern Yellow Pine

2021 ◽  
Vol 71 (3) ◽  
pp. 199-208
Author(s):  
Qingzheng Cheng ◽  
Juliet D. Tang ◽  
Chengfeng Zhou ◽  
Wei Jiang ◽  
Lixia Hu ◽  
...  
Keyword(s):  
Weight Loss ◽  
Moisture Content ◽  
Oriented Strand Board ◽  
Soy Flour ◽  
Water Repellent ◽  
Rating Data ◽  
Structural Applications ◽  
Choice Tests ◽  
Yellow Pine ◽  
Southern Yellow Pine

Abstract Soy flour was evaluated as a partial substitute for resin in the manufacture of oriented strand board (OSB), a wood-based composite that often replaces solid lumber and plywood in structural applications in the construction industry. Since the presence of soy could alter OSB biodegradation properties, termite resistance of OSB panels made with 0, 10, and 20 percent of polymeric methylene diphenyl diisocyanate (pMDI) resin substituted with soy flour (OSB0, OSB10, and OSB20, respectively) was investigated. Single choice tests between three types of OSB and southern yellow pine (SYP) solid wood and an OSB choice test (OSB0 vs. OSB10) were evaluated. Results indicated that termites always showed a preference for SYP, with the OSB becoming less palatable when soy flour was present. Percentage weight losses for OSB0, OSB10, and OSB20 were 5.7×, 8.4×, and 8.6× less, respectively, compared with SYP. In the absence of SYP, termites did not differentiate OSB0 from OSB10, with OSB10 showing 1.5× less weight loss compared with OSB0. Visual rating data supported weight loss data, except significantly less damage was only found when the choice paired SYP with OSB made with soy (OSB10 or OSB20). Termite consumption preference for SYP was explained by differences in water absorption kinetics. SYP reached saturation (105% moisture content) within 1 week on moist sand, while moisture content of OSB composites slowly climbed to 79 percent over 4 weeks, never reaching a plateau. Lower moisture content was due to the presence of water-repellent resin and wax in the OSB.

Renewable resources-based PTT [poly(trimethylene terephthalate)]/switchgrass fiber composites: The effect of compatibilization

2012 ◽  
Vol 85 (3) ◽  
pp. 521-532 ◽  
Author(s):  
Jeevan Prasad Reddy ◽  
Manjusri Misra ◽  
Amar Mohanty
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Renewable Resources ◽  
Melt Flow Index ◽  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Flow Index ◽  
Methylene Diphenyl Diisocyanate ◽  
Trimethylene Terephthalate ◽  
The Impact

In this research, switchgrass (SG) fiber-reinforced poly(trimethylene terephthalate) (PTT) biocomposites were prepared by extrusion followed by injection molding machine. The methylene-diphenyl-diisocyanate-polybutadiene (MDIPB) prepolymer was used to enhance the impact strength of the biocomposites. In addition, the polymeric methylene-diphenyl-diisocyanate (PMDI) compatibilizer was used to enhance the mechanical properties of the composites. The effect of compatibilizer on mechanical, crystallization melting, thermomechanical, melt flow index (MFI), morphological, and thermal stability properties of the composites was studied. Thermomechanical properties of the biocomposites were studied by dynamic mechanical analysis (DMA). Scanning electron microscopy (SEM) was used to observe the interfacial adhesion between the fiber and matrix. The results showed that MDIPB and PMDI have a significant effect on the mechanical properties of the composites. The impact strength of MDIPB- and PMDI-compatibilized composites was increased by 87 % when compared to the uncompatibilized composite.

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