Application of Liquefied Wood to a New Resin System—Synthesis and Properties of Liquefied Wood/Epoxy Resins

Holzforschung ◽  
2000 ◽  
Vol 54 (1) ◽  
pp. 93-97 ◽  
Author(s):  
Masahiko Kobayashi ◽  
Kyoko Tukamoto ◽  
Bunichiro Tomita
Keyword(s):  
Glass Transition ◽  
Epoxy Resins ◽  
Polymer Networks ◽  
Resin System ◽  
Optimum Conditions ◽  
Mechanical Measurement ◽  
Liquefied Wood ◽  
Dynamic Mechanical Measurement ◽  
Film Forming ◽  
Wood Content

Summary A new resin system was developed by reacting liquefied wood with various epoxy compounds. Examination of the optimum conditions for the synthesis of the resins, and the behavior of liquefied wood in the cured resins were undertaken. Generally, the compatibility and film forming performance of liquefied wood/epoxy resins became better as the wood content increased. The presence of only one broad dispersion peak, due to the glass transition, was observed during dynamic mechanical measurement of resin films suggesting that the different components of the resin were compatible. The glass transition temperature of the cured resins could be modified by changing the kinds of epoxy compounds and the wood contents of liquefied wood. The presence of rubber elasticity at higher temperatures suggests that the resin systems consisted of cross-linking polymer networks.

Epoxy Resin Embedment

1968 ◽  
Vol 26 ◽  
pp. 100-101
Author(s):  
J. G. Adams ◽  
M. M. Campbell ◽  
H. Thomas ◽  
J. J. Ghldonl
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Epoxy Resin ◽  
Light Microscope ◽  
Epoxy Resins ◽  
Image Contrast ◽  
Tissue Preservation ◽  
Resin System ◽  
Excellent Quality

Since the introduction of epoxy resins as embedding material for electron microscopy, the list of new formulations and variations of widely accepted mixtures has grown rapidly. Described here is a resin system utilizing Maraglas 655, Dow D.E.R. 732, DDSA, and BDMA, which is a variation of the mixtures of Lockwood and Erlandson. In the development of the mixture, the Maraglas and the Dow resins were tested in 3 different volumetric proportions, 6:4, 7:3, and 8:2. Cutting qualities and characteristics of stability in the electron beam and image contrast were evaluated for these epoxy mixtures with anhydride (DDSA) to epoxy ratios of 0.4, 0.55, and 0.7. Each mixture was polymerized overnight at 60°C with 2% and 3% BDMA.Although the differences among the test resins were slight in terms of cutting ease, general tissue preservation, and stability in the beam, the 7:3 Maraglas to D.E.R. 732 ratio at an anhydride to epoxy ratio of 0.55 polymerized with 3% BDMA proved to be most consistent. The resulting plastic is relatively hard and somewhat brittle which necessitates trimming and facing the block slowly and cautiously to avoid chipping. Sections up to about 2 microns in thickness can be cut and stained with any of several light microscope stains and excellent quality light photomicrographs can be taken of such sections (Fig. 1).

scholarly journals Investigation of the functional network modifier loading on the stoichiometric ratio of epoxy resins and their dielectric properties

2021 ◽  
Author(s):  
Istebreq A. Saeedi ◽  
Sunny Chaudhary ◽  
Thomas Andritsch ◽  
Alun S. Vaughan
Keyword(s):  
Glass Transition ◽  
Dielectric Properties ◽  
Electrical Properties ◽  
Epoxy Resins ◽  
Functional Network ◽  
Cross Linking ◽  
Network Modifier ◽  
Epoxy Resin System ◽  
The Cross ◽  
The Impact

AbstractReactive molecular additives have often been employed to tailor the mechanical properties of epoxy resins. In addition, several studies have reported improved electrical properties in such systems, where the network architecture and included function groups have been modified through the use of so-called functional network modifier (FNM) molecules. The study reported here set out to investigate the effect of a glycidyl polyhedral oligomeric silsesquioxane (GPOSS) FNM on the cross-linking reactions, glass transition, breakdown strength and dielectric properties of an amine-cured epoxy resin system. Since many previous studies have considered POSS to act as an inorganic filler, a key aim was to consider the impact of GPOSS addition on the stoichiometry of curing. Fourier transform infrared spectroscopy revealed significant changes in the cross-linking reactions that occur if appropriate stoichiometric compensation is not made for the additional epoxide groups present on the GPOSS. These changes, in concert with the direct effect of the GPOSS itself, influence the glass transition temperature, dielectric breakdown behaviour and dielectric response of the system. Specifically, the work shows that the inclusion of GPOSS can result in beneficial changes in electrical properties, but that these gains are easily lost if consequential changes in the matrix polymer are not appropriately counteracted. Nevertheless, if the system is appropriately optimized, materials with pronounced improvements in technologically important characteristics can be designed.

scholarly journals Strengthening epoxy adhesives at elevated temperatures based on dynamic disulfide bonds

2020 ◽  
Vol 1 (9) ◽  
pp. 3182-3188
Author(s):  
Hsing-Ying Tsai ◽  
Yasuyuki Nakamura ◽  
Takehiro Fujita ◽  
Masanobu Naito
Keyword(s):  
Glass Transition ◽  
Disulfide Bonds ◽  
Epoxy Resins ◽  
Elevated Temperatures ◽  
Adhesive Properties ◽  
Epoxy Adhesives ◽  
Transition Points ◽  
Increasing Temperature

Epoxy resins incorporating aromatic disulfide bonds demonstrated improved adhesive properties with increasing temperature below their glass transition points.

Synthesis of epoxy resins from alcohol-liquefied wood and the mechanical properties of the cured resins

2010 ◽  
Vol 120 (2) ◽  
pp. 745-751 ◽  
Author(s):  
Hajime Kishi ◽  
Yuki Akamatsu ◽  
Masayuki Noguchi ◽  
Akira Fujita ◽  
Satoshi Matsuda ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Epoxy Resins ◽  
Liquefied Wood

Ability to Control the Glass Transition Temperature of Amorphous Shape-Memory Polyesterurethane Networks by Varying Prepolymers in Molecular Mass as well as in Type and Content of Incorporated Comonomers

2009 ◽  
Vol 1190 ◽  
Author(s):  
Joerg Zotzmann ◽  
Steffen Kelch ◽  
Armin Alteheld ◽  
Marc Behl ◽  
Andreas Lendlein
Keyword(s):  
Glass Transition ◽  
Minimally Invasive Surgery ◽  
Shape Memory ◽  
Molecular Mass ◽  
Amorphous Polymer ◽  
Polymer Networks ◽  
Precise Control ◽  
Low Weight ◽  
Switching Temperature ◽  
Selection Of

AbstractThe need of intelligent implant materials for applications in the area of minimally invasive surgery leads to tremendous attention for polymers which combine degradability and shape-memory capability. Application of heat, and thereby exceeding a certain switching temperature Tsw, causes the device to changes its shape. The precise control of Tsw is particularly challenging. It was investigated in how far Tg, that can be used as Tsw, of amorphous polymer networks from star-shaped polyester macrotetrols crosslinked with a low-weight linker can be controlled systematically by incorporation of different comonomers into poly(rac-lactide) prepolymers. The molecular mass of the prepolymers as well as type and content of the comonomers was varied. The Tg could be adjusted by selection of comonomer type and ratio without affecting the advantageous elastic properties of the polymer networks.

Study on the Composites Epoxy Resin/Nano-TiO2/Polyester

2013 ◽  
Vol 787 ◽  
pp. 408-412
Author(s):  
Jiao Yan Ai ◽  
Quan Chen ◽  
Xiao Bo Wang
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Epoxy Resin ◽  
Diethylene Glycol ◽  
Epoxy Resins ◽  
Experimental Results ◽  
Hydroxybenzoic Acid ◽  
Suitable Amount

Two kinds of polyester bis (p-hydroxybenzoic acid) butanediolatepolyester (BDPET) and bis (p-hydroxybenzoic acid) diethylene glycol (DGPET) were synthesized through melting transesterification reaction.Then the epoxy resins were modified with BDPET or DGPET,and nanoTiO2. The composites were characterized by DSC and SEM. The experimental results showed that the polyester can act as an effective toughening modifier for the epoxy resin. The mechanical properties of the composites were greatly improved and reached to the maxium at 4wt.%PET. The PET/EP system modified by adding suitable amount of nanoTiO2have better performance.The glass transition temperature (Tg) of PET/EP and nanoTiO2/PET/EP system improved about 20°Cand 27.8°C,respectively.

Processing and Characterization of Hybrid Nanoparticle Infused Structural Fiber Composites

Materials ◽  
2005 ◽  
Author(s):  
Oladapo Akinyede ◽  
Ram Mohan ◽  
Ajit Kelkar ◽  
Jag Sankar ◽  
Ashish Pandya
Keyword(s):  
Glass Transition ◽  
Epoxy Resin ◽  
Composite Laminates ◽  
Gravimetric Analysis ◽  
Structural Level ◽  
Resin System ◽  
Epoxy Resin System ◽  
Alumina Oxide ◽  
Oxide Particles ◽  
Modified Resin

Effective conventional manufacturing techniques are required to integrate the nanomaterial configurations into material systems at a larger component and structural level to obtain the enhanced benefits offered by the material configurations at the nano length scale. A low cost manufacturing process based on vacuum assisted resin transfer molding (VARTM) is demonstrated for the effective processing of fiber composite laminates using modified epoxy resin systems dispersed with nano and sub-micron alumina oxide particles. The effect of alumina oxide particles on the thermo physical properties (glass transition temperature, etc), are studied via differential scanning calorimetry and thermal gravimetric analysis. Higher glass transition temperatures with the alumina oxide and other nano particulate systems provide an opportunity to use conventional resin systems in high temperature applications. Ultrasonic mixing is employed to uniformly disperse the particles into an epoxy resin system. The flow characteristics of the modified resin system are not significantly different than the neat resin system and allowed the use of traditional VARTM processes successfully. The details of the resin modification and current studies on particulate modification for better interfacial bond are discussed in this paper. Wear performance for reinforced plastics are also investigated in this paper. Composite laminates with S2 glass and modified resins are fabricated. The mechanical behavior of the fabricated composite laminates with the neat and modified resin system using different sized and loading of alumina oxide particles are presented and discussed.

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