Cure kinetics of aqueous phenol–formaldehyde resins used for oriented strandboard manufacturing: Effect of zinc borate

2006 ◽  
Vol 101 (6) ◽  
pp. 3886-3894 ◽  
Author(s):  
Yong Lei ◽  
Qinglin Wu
Holzforschung ◽  
2010 ◽  
Vol 64 (5) ◽  
Author(s):  
Yi Wang ◽  
Vikram Yadama ◽  
Marie-Pierre Laborie ◽  
Debes Bhattacharyya

Abstract In thermoforming of profiled wood-strand composites, an adhesive system is needed to provide a weak initial bond to maintain mat integrity and architecture during the forming process and eventually a durable bond when the final cross-sectional shape is achieved. A hybrid adhesive composed of phenol formaldehyde (PF) and poly(vinyl acetate) (PVAc) is proposed in this study. The cure kinetics of this hybrid adhesive and bond development in a multi-step hot-pressing is discussed. Cure kinetics studied by differential scanning calorimetry indicated that adding PVAc slowed down the curing reaction of PF resin; however, the full cure of PF was not inhibited. The nth-order Borchardt Daniels (nth-BD) model provided good prediction for the curing of adhesives with a PF/PVAc ratio lower than 1:1. To simulate roll forming of wood-strand mats, a hot-pressing schedule at low temperature combined with multi-stage closing and opening was developed. The nth-BD model was able to predict the actual bond development for composites made with neat PF resin. The results indicated that cure kinetics of a PF/PVAc hybrid adhesive would not significantly differ from neat PF resin for blend ratios of 1:1 or lower, thus potentially providing a resin system for roll forming or matched-die forming of wood-strand composites.


2005 ◽  
Vol 439 (1-2) ◽  
pp. 68-73 ◽  
Author(s):  
Jinwu Wang ◽  
Marie-Pierre G. Laborie ◽  
Michael P. Wolcott

2008 ◽  
Vol 108 (3) ◽  
pp. 1837-1844 ◽  
Author(s):  
Hui Pan ◽  
Todd F. Shupe ◽  
Chung-Yun Hse

2021 ◽  
pp. 002199832110015
Author(s):  
Alexander Vedernikov ◽  
Yaroslav Nasonov ◽  
Roman Korotkov ◽  
Sergey Gusev ◽  
Iskander Akhatov ◽  
...  

Pultrusion is a highly efficient composite manufacturing process. To accurately describe pultrusion, an appropriate model of resin cure kinetics is required. In this study, we investigated cure kinetics modeling of a vinyl ester pultrusion resin (Atlac 430) in the presence of aluminum hydroxide (Al(OH)3) and zinc stearate (Zn(C18H35O2)2) as processing additives. Herein, four different resin compositions were studied: neat resin composition, composition with Al(OH)3, composition comprising Zn(C18H35O2)2, and composition containing both Al(OH)3 and Zn(C18H35O2)2. To analyze each composition, we performed differential scanning calorimetry at the heating rates of 5, 7.5, and 10 K/min. To characterize the cure kinetics of Atlac 430, 16 kinetic models were tested, and their performances were compared. The model based on the [Formula: see text]th-order autocatalytic reaction demonstrated the best results, with a 4.5% mean squared error (MSE) between the experimental and predicted data. This study proposes a method to reduce the MSE resulting from the simultaneous melting of Zn(C18H35O2)2. We were able to reduce the MSE by approximately 34%. Numerical simulations conducted at different temperatures and pulling speeds demonstrated a significant influence of resin composition on the pultrusion of a flat laminate profile. Simulation results obtained for the 600 mm long die block at different die temperatures (115, 120, 125, and 130 °C) showed that for a resin with a final degree of cure exceeding 95% at the die exit, the maximum difference between the predicted values of pulling speed for a specified set of compositions may exceed 1.7 times.


2019 ◽  
Vol 136 ◽  
pp. 105290 ◽  
Author(s):  
Maryam Jouyandeh ◽  
Zohre Karami ◽  
Samir M. Hamad ◽  
Mohammad Reza Ganjali ◽  
Vahideh Akbari ◽  
...  

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