scholarly journals Effect of Boron and Phosphorus Compounds on Fire and Technological Properties of Oriented Strandboard

2020 ◽  
Vol 2 (2) ◽  
pp. 117-122

Effects of various fire retardant chemicals on fire and technological properties of laboratory made oriented strandboards (OSBs) were investigated. Aspen chips were used in the production of OSB panels. An exterior liquid phenol formaldehyde resin with 47 percent solid content was used as adhesive. There was no addition of any hardener and filling materials into resin in the OSB manufacturing. Boron compounds such as borax and boric acid, and phospate compounds such as monoammonium phosphate and diammonium phospahate were used as fire retardant chemicals in the OSB panels. An exterior liquid phenol formaldehyde resin was used as adhesive. The chemicals in powder form were added into the resin blender at contents of 2%, 4%, and 6% based on oven-dry wood weight. The OSB panels containing borax had the highest thickness swelling, followed by the panels containing boric acid, monoammonium phospahate, and diammonium phosphate, respectively. Increasing the content of these chemicals in the OSB resulted in greater thickness swelling. For the mechanical properties, the chemicals can be used up to oven dry particle weight of 6% in the panels at humid and dry conditions because of the fact that they met the standard values of mechanical properties given in TS EN 300 for types of OSB/3 (exterior type. Fire resistance of the panels was improved with increased chemical content in the panels.

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.


BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 5422-5435
Author(s):  
Sena Maulana ◽  
Wahyu Hidayat ◽  
Ihak Sumardi ◽  
Nyoman J. Wistara ◽  
Muhammad I. Maulana ◽  
...  

Physical and mechanical properties were evaluated for bamboo-oriented strand boards (BOSB) prepared with combinations of two contrasting bamboo species and bonded with phenol formaldehyde resin under various compression ratios. The strands from the culms of Gigantochloa pseudoarundinacea and Dendrocalamus asper bamboo were steam-treated at a temperature of 126 °C and a pressure of 0.14 MPa for 1 h and then washed with a 1% NaOH solution. Three-layer dual-species bamboo-oriented strand boards with a shelling ratio of 25 to 50 to 25 (face to core to back) were manufactured with different compression ratios using an 8% phenol formaldehyde adhesive and 1% paraffin. The slenderness ratio and aspect ratio were evaluated by measuring 100 random strands to determine uniformity. The solidity profiles of the dual-species bamboo-oriented strand boards (thickness direction) were relatively uniform. The modulus of rupture, modulus of elasticity, and internal bond values of the dual-species bamboo-oriented strand boards increased as the compression ratio increased, but the water absorption and thickness swelling decreased. The dual-species bamboo-oriented strand boards prepared with compression ratios of 1.44 to 1.25 and 1.54 to 1.33 met all the requirements of CSA standard 0437 (2011). The optimum compression ratio for the preparation of dual-species bamboo-oriented strand boards was 1.44 to 1.25.


2019 ◽  
Vol 26 (3) ◽  
Author(s):  
Viviane Teixeira Iwakiri ◽  
Rosilani Trianoski ◽  
Dalton Luiz Razera ◽  
Setsuo Iwakiri ◽  
Thiago Souza da Rosa

ABSTRACT The objective of this work was to evaluate the feasibility of using lignin-phenol-formaldehyde resin in the production of Mimosa scabrella Benth (bracatinga) structural particleboard. The boards were produced with nominal specific mass of 0.75 and 0.95 g/cm3, 10% and 12% of phenol-formaldehyde and lignin-phenol-formaldehyde resins, with 10 and 12 min of pressing time. The boards quality was evaluated by means of the following physical-mechanical tests: specific mass, compression ratio, water absorption and thickness swelling after 2 and 24 hours soaking, perpendicular traction, static bending and screw pulling. Positive interactions of specific mass, resin content and pressing time were observed in the properties of the boards produced. The evaluation of the properties results based on the requirements of EN 312 (type P5) standard indicated the feasibility of using lignin-phenol-formaldehyde resin in the production of particleboard of Mimosa scabrellla for structural applications.


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.


Forests ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 84 ◽  
Author(s):  
Susanne Bollmus ◽  
Cara Beeretz ◽  
Holger Militz

This study deals with the influence of chemical modification on elasto-mechanical properties of Scots pine (Pinus sylvestris L.). The elasto-mechanical properties examined were impact bending strength, determined by impact bending test; tensile strength; and work to maximum load in traction, determined by tensile tests. The modification agents used were one melamine-formaldehyde resin (MF), one low molecular weight phenol-formaldehyde resin, one higher molecular weight phenol-formaldehyde resin, and a dimethylol dihydroxyethyleneurea (DMDHEU). Special attention was paid to the influence of the solution concentration (0.5%, 5%, and 20%). With an increase in the concentration of each modification agent, the elasto-mechanical properties decreased as compared to the control specimens. Especially impact bending strength decreased greatly by modifications with the 0.5% solutions of each agent (by 37% to 47%). Modification with DMDHEU resulted in the highest overall reduction of the elasto-mechanical properties examined (up to 81% in work to maximum load in traction at 20% solution concentration). The results indicate that embrittlement is not primarily related to the degree of modification depended on used solution concentration. It is therefore assumed that molecular size and the resulting ability to penetrate into the cell wall could be crucial. The results show that, in the application of chemically modified wood, impact and tensile loads should be avoided even after treatment with low concentrations.


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