Epoxy Resins and Phenol-Formaldehyde Resins

2012 ◽  
pp. 723-751 ◽  
Author(s):  
T. Takeichi ◽  
N. Furukawa
Keyword(s):  
Epoxy Resins ◽  
Phenol Formaldehyde

Lignin-based adhesive crosslinked by furfuryl alcohol–glyoxal and epoxy resins

2019 ◽  
Vol 34 (2) ◽  
pp. 228-238 ◽  
Author(s):  
Jun Zhang ◽  
Wenli Wang ◽  
Xiaojian Zhou ◽  
Jiankun Liang ◽  
Guanben Du ◽  
...  
Keyword(s):  
Furfuryl Alcohol ◽  
Epoxy Resins ◽  
Phenol Formaldehyde ◽  
Laser Desorption ◽  
Laser Desorption Ionization ◽  
Ionization Time ◽  
Oh Groups ◽  
Acidic Conditions ◽  
Matrix Assisted Laser ◽  
Better Than

Abstract In this work, a novel environmentally friendly lignin-based adhesive crosslinked with a furfuryl alcohol–glyoxal resin and epoxy resin (EPR) was used to bond particleboard. The results of 13C nuclear magnetic resonance and matrix-assisted laser desorption–ionization time-of-flight mass spectroscopy indicated that furfuryl alcohol and glyoxal reacted under acidic conditions and that–CH–(OH)–groups may be involved in the crosslinking of the lignin–furfuryl–glyoxal resin, which also easily crosslinked with EPR. The IB strength of the particleboard bonded with LFG + 9 % EPR adhesive was better than that of the particleboard bonded with lignin–furfuryl alcohol (LF) adhesive. Moreover, the modulus of elasticity of the LFG + 9 % EPR adhesive was higher than that of the LF and phenol-formaldehyde adhesives.

Polymer Modified Bitumen: Review

2016 ◽  
Vol 10 (4s) ◽  
pp. 631-636 ◽  
Author(s):  
Serhiy Pyshyev ◽  
◽  
Volodymyr Gunka ◽  
Yuriy Grytsenko ◽  
Michael Bratychak ◽  
...  
Keyword(s):  
Epoxy Resins ◽  
Phenol Formaldehyde ◽  
Thermoplastic Elastomers ◽  
Modified Bitumen ◽  
Reactive Polymers ◽  
Polymer Modified Bitumen ◽  
Bitumen Modification ◽  
Polymer Modifiers

The main reasons and ways of bitumen modification by polymers were examined. Positive and negative aspects of the usage of different polymer modifiers (elastomers, thermoplastic elastomers, reactive polymers, thermoplastics) were analysed. The authors’ achievements concerning modification of bitumen by various polymers, namely indene-coumarone, petroleum, phenol-formaldehyde and epoxy resins, were described.

Effect of stoichiometric ratios for synthesized epoxy phenolic novolac (EPN) resins on their physicochemical, thermomechanical and morphological properties

2016 ◽  
Vol 45 (4) ◽  
pp. 265-279 ◽  
Author(s):  
Abhishek Das ◽  
Gautam Sarkhel
Keyword(s):  
Epoxy Resin ◽  
Epoxy Resins ◽  
Phenol Formaldehyde ◽  
Protective Coatings ◽  
Stoichiometric Composition ◽  
Morphological Properties ◽  
Mechanical And Thermal Properties ◽  
Content Type ◽  
Structural Applications ◽  
Stoichiometric Ratios

Purpose The purpose of this paper is to study the effect of various stoichiometric ratios for synthesised epoxy phenolic novolac (EPN) resins on their physicochemical, thermomechanical and morphological properties. Design/methodology/approach In the present study, EPN (EPN-1, EPN-2, EPN-3, EPN-4 and EPN-5) resins were synthesised by varying five types of different stoichiometric ratios for phenol/formaldehyde along with the corresponding molar ratios for novolac/epichlorohydrin. Their different physicochemical properties of interest, thermomechanical properties as well as morphological properties were studied by means of cured samples with the variation of its stoichiometric ratios. Findings The average functionality and reactivity of EPN resin can be controlled by controlling epoxy equivalence as well as cross-linking density upon its curing as all of these factors are internally correlated with each other. Research limitations/implications Epoxy resins are characterised by a three-membered ring known as the epoxy or oxirane group. The capability of the epoxy ring to react with a variety of substrates imparts versatility to the resin. However, these resins have a major drawback of low toughness, and they are also very brittle, which limits their application in products that require high impact and fracture strength. Practical implications Epoxy resins have been widely used as high-performance adhesives and matrix resins for composites because of their outstanding mechanical and thermal properties. Because of their highly cross-linked structure, the epoxy resin disables segmental movement, making them hard, and it is also notch sensitive, having very low fracture energy. Social implications Epoxy resin is widely used in industry as protective coatings and for structural applications, such as laminates and composites, tooling, moulding, casting, bonding and adhesives. Originality/value Systematic study has been done for the first time, as no exact quantitative stoichiometric data for the synthesis of EPN resin were available on the changes of its different properties. Thus, an optimised stoichiometric composition for the synthesis of the EPN resin was found.

scholarly journals Mechanical properties (Tensile, Hardness and Shock resistance) for the phenol formaldehyde resin with Epoxy resin

2019 ◽  
Vol 12 (2) ◽  
pp. 35-43
Author(s):  
Mustafa A. Rajab
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Composite Materials ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Phenol Formaldehyde ◽  
Phenol Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Shock Resistance

Phenolic formaldehyde (resole) resin was used at a different weight (10%, 20%, 30%, 40%), with epoxy resins at varying percentages (90%, 80%, 70%, 60%) at 20 C °. In order to study the mechanical properties (which including: Tensile strength, hardness and shock resistance), for the purpose of analysis and comparison with the mechanical properties of alloys, and the selected part for the purpose of replacing the alloy with the composite materials to reduce weight and improve mechanical properties. The results indicate improved properties with increased epoxy resins due to increased bonding between components.

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).

Technical notes on routine TEM procedures

1987 ◽  
Vol 45 ◽  
pp. 630-631
Author(s):  
K. Chien ◽  
R.L. Van de Velde ◽  
R.C. Heusser
Keyword(s):  
Epoxy Resins ◽  
Pathology Laboratory ◽  
Silicone Fluid ◽  
Image Position

Sectioning quality of epoxy resins can be improved by the addition of a 1% silicone 200 fluid (Dow Corning), however this produces a softer block. To compensate, a harder plastic has been used for embedding various tissues encountered in our pathology laboratory. Exact amounts of the plastic mixture can be directly made up for embedding as shown: The chart reveals a Poly/Bed 812 (WPE 145) to anhydride ratio of 1:0.7 and a NMA to DDSA ratio of 7:3. 1% silicone fluid is added to above mixtures.Due to impurities within the DDSA and NMA, the polymerized epoxy blocks vary in darkness and appear to affect sectioning quality. After discussing this problem with Polysciences Inc., they have agreed to purify their anhydrides in an effort to standardize the consistency of the plastic.

Stain contamination and embedding in electron microscopy

1986 ◽  
Vol 44 ◽  
pp. 50-53
Author(s):  
Hilton H. Mollenhauer
Keyword(s):  
Electron Microscopy ◽  
Information Retrieval ◽  
Epoxy Resins ◽  
Image Contrast ◽  
Sample Preservation ◽  
Factors Associated ◽  
Amount Of Information ◽  
Electron Microscopical ◽  
Contrast Information

Many factors (e.g., resolution of microscope, type of tissue, and preparation of sample) affect electron microscopical images and alter the amount of information that can be retrieved from a specimen. Of interest in this report are those factors associated with the evaluation of epoxy embedded tissues. In this context, informational retrieval is dependant, in part, on the ability to “see” sample detail (e.g., contrast) and, in part, on tue quality of sample preservation. Two aspects of this problem will be discussed: 1) epoxy resins and their effect on image contrast, information retrieval, and sample preservation; and 2) the interaction between some stains commonly used for enhancing contrast and information retrieval.

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