scholarly journals Synthesis, Characterization and Mechanical Evaluation of the Phenol-Formaldehyde Composites

2008 ◽  
Vol 5 (s1) ◽  
pp. S1015-S1020 ◽  
Author(s):  
B. S. Kaith ◽  
Aashish Chauhan

Phenol: formaldehyde ratio was varied in the synthesis of phenol- formaldehyde resin and used to prepare the composites. These composites were then evaluated for their mechanical strength on the basis of tensile strength, compressive strength and wear resistance. Composite with better strength was characterized by IR, SEM, XRD, TGA/DTA and further studies were carried out for its physico-chemical and mechanical properties like viscosity, modulus of rupture (MOR), modulus of elasticity (MOE) and stress at the limit of proportionality (SP)etc.

Author(s):  
D. A. Brazhnik ◽  
G. D. Semchenko ◽  
G. N. Shabanova ◽  
E. E. Starolat ◽  
I. N. Rozhko ◽  
...  

The possibilities of improving the physico-mechanical properties of periclase-carbon materials by modifying the phenol-formaldehyde resin (PFR) with organoinorganic complexes are described. The composition of the modifying additives, the phase composition of the materials after the PFR hardening are given, the influence of modifiers on the formation of the structure of materials is established. It is shown that the introduction of ethyl silicate or hydrolyzed ethyl silicate into liquid PFR during preparation of the charge contributes to the formation of SiC in the phase composition. The conclusion is made about the rationality of the introduction of ethyl silicate in an amount of from 0,66 to 1 wt. % and the prospects of introducing nickel oxalate into a liquid PFR together with ammonium citrate to increase the compressive strength of periclase-carbon materials up to 60 MPa. Ill. 7. Ref. 9.


2021 ◽  
Vol 17 (2) ◽  
pp. 152-159
Author(s):  
Rynaldo Davinsy ◽  
Sena Maulana ◽  
Muhammad I Maulana ◽  
Elvara D Satria ◽  
Deded S Nawawi ◽  
...  

Hybrid Bamboo Oriented Strand Boards (OSB) were produced to improve bamboo OSB's physical and mechanical properties. Shelling ratio adjustment of the strand type combination could determine the optimal physical and mechanical properties of hybrid bamboo oriented strand boards (OSB). The purpose of this study was to evaluate the physical and mechanical properties of hybrid betung and andong bamboos OSB at various shelling ratios. Steam modified strands of betung and andong bamboo were used as an outer layer and core layer, respectively. Hybrid bamboo OSBs were prepared with 0.7 g cm-3 target density and 8% phenol-formaldehyde resin content. Three layers of OSB were made with outer: core shelling ratios of 30:70, 40:60, 50:50, and 60:40. The physical and mechanical properties of the OSB were tested referring to the JIS A 5908-2003 standard. The targeted board density was achieved and the physical properties of all hybrid bamboo OSB have met the requirement of CSA O437.0 (Grade O-1) standard criteria. The parallel modulus of elasticity (MOE) and modulus of rupture (MOR) increased with increasing outer layer ratio. However, the perpendicular MOE and MOR decreased with increasing outer layer ratio. The internal bonding (IB) of the OSB with a shelling ratio of 30:70 and 40:60 met with the requirement of the CSA O437.0 (Grade O-1) standard.


2019 ◽  
Vol 12 (2) ◽  
pp. 35-43
Author(s):  
Mustafa A. Rajab

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.


2008 ◽  
Vol 5 (1) ◽  
pp. 177-184 ◽  
Author(s):  
Susheel Kalia ◽  
B. S. Kaith

Graft copolymers of methyl methacrylate (MMA) and its binary mixtures such as MMA + ethyl acrylate (EA), MMA + acrylonitrile (AN), MMA + acrylic acid (AA), MMA + vinyl acetate (VA), MMA + acrylamide (AAm) and MMA + styrene (Sty) with flax fiber have been prepared in air (IA) and under the influence of microwave radiations (MWR). Synthesized flax-g-copolymers under two different reaction conditions were used as reinforcing material in the preparation of phenol-formaldehyde composites. Mechanical properties such as wear resistance, modulus of rupture (MOR), modulus of elasticity (MOE) and stress at the limit of proportionality (SP) were measured and a comparative studied has been made. It has been found that composites reinforced with flax-g-copolymers-MWR showed better mechanical properties in comparison to composites reinforced with flax-g-copolymers-IA


2008 ◽  
Vol 1 (2) ◽  
pp. 113-120 ◽  
Author(s):  
A. C. Marques ◽  
J. L. Akasaki ◽  
A. P. M. Trigo ◽  
M. L. Marques

In this work it was evaluated the influence tire rubber addition in mortars in order to replace part of the sand (12% by volume). It was also intended to verify if the tire rubber treatment with NaOH saturated aqueous solution causes interference on the mechanical properties of the mixture. Compressive strength, splitting tensile strength, water absorption, modulus of elasticity, and flow test were made in specimens of 5cmx10cm and the tests were carried out to 7, 28, 56, 90, and 180 days. The results show reduction on mechanical properties values after addition of tire rubber and decrease of the workability. It was also observed that the tire rubber treatment does not cause any alteration on the results compared to the rubber without treatment.


1994 ◽  
Vol 370 ◽  
Author(s):  
Manouchehr Hassanzadeh

AbstractThis study has determined the fracture mechanical properties of 9 types of rock, namely fine-, medium- and coarse-grained granites, gneiss, quartzite, diabase, gabbro, and fine- and coarse-grained limestones. Test results show among other things that quartzite has the highest compressive strength and fracture energy, while diabase has the highest splitting tensile strength and modulus of elasticity. Furthermore, the strength and fracture energy of the interfacial zone between the rocks and 6 different mortars have been determined. The results showed that, in this investigation, the mortar/rock interfaces are in most cases weaker than both mortars and rocks.


2011 ◽  
Vol 217-218 ◽  
pp. 490-494
Author(s):  
Gai Yun Li ◽  
Te Fu Qin

The waste brown-rotted wood was liquefied in phenol with phosphoric acid as a catalyst and the resulting liquefied products were condensed with formaldehyde to yield novolak liquefied wood-based phenol formaldehyde resin (LWF). The results showed that brown-rotted wood could be almost completely liquefied within 0.5 h at phenol to wood (P/W) ratio 2. An increase in P/W ratio from 2 to 3 slightly improved the flow property of LWF, but accompanied by decreasing the product yield from approximately 140 to 120 %. The increase of liquefaction time from 30 min to 60 min did not have a significant influence on the resulting LWF. The thermofluidity of LWF were compared to that of the commercial novolak PF resin, and could be used to make moldings with similar thermal property and mechanical properties to those obtained from the conventional novolak PF resin.


2020 ◽  
Vol 57 (1) ◽  
pp. 28-36
Author(s):  
Vasiliy Cherkasov ◽  
Yuiy Yurkin ◽  
Valeriy Avdonin ◽  
Dmitriy Suntsov

It is actual now to work out new radiation protecting sheeting on the basis of non-curing polymeric composition which possess self-adhesion properties, are easily mounted and dismantled and provide high tightness and low permeability. Mechanical properties of non-curing composites consisting of ethylene propylene diene monomer (EPDM), industrial oil (IO), alkyl phenol-formaldehyde resin (PF) with addition of barite (52 %) to the total material volume were investigated in this article. The aim of investigation is to find optimal content of the above mentioned components at which it would be possible to get the following properties: composite would be sticky enough (peel strength not less than 4 N/cm); character of a separation would be cohesive (on a material) and thus there would be no migration of softener and satisfactory resistance of fluidity. The results showed that PF addition till 20 % in the system EPDM/PF leads to the increasing of adhesive strength, in this case optimal oil concentration in the system EPDM/PF/IO is in the interval from 45 till 55 %. New self-adhesion lead-free material, exhibited higher X-ray-shielding properties, is also received in the result of investigation.


Author(s):  
Sajid Mehmood ◽  
Faheem Butt

This study investigated the effects of steel fibers on the fresh and hardened properties, and heat of hydration of concrete containing FA (Fly Ash). A total of 192 samples were cast comprising cubes, cylinders, and prisms, for six concrete mixes with varying contents of steel fibers by volume and a fixed content of FA i.e. 15% by weight of cement. The semi adiabatic setup was used to monitor temperature rise due to the heat of hydration in the concrete mixes for fourteen days. The use of FA increased workability, and decreased early compressive strength, tensile strength and heat of hydration of concrete. However, an increase in the compressive strength of FA concrete was observed by the addition of steel fibers up to 0.9% whereas a consistent increase in the splitting tensile strength and modulus of rupture was observed with the addition of the steel fibers from 0.4-1.8%. Further the test results showed that increasing steel fibers content decrease the evolution of heat due to hydration. It was concluded that the FA concrete with steel fibers can be used in precast industry and mass construction projects due to the improved mechanical properties and lower heat of hydration.


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