نتایج جستجو برای: urea formaldehyde resin

تعداد نتایج: 77915  

2013
Wubin Ding Wenyan Li Qiang Gao Chunrui Han Shifeng Zhang

Urea-formaldehyde (UF) resin (F/U: 1.25), melamine-urea-formaldehyde (MUF) resin (F/(U+M): 1.05), and three kinds of wood species including poplar (Populus davidiana Dode), beech (Fagus engleriana Seem.), and eucalyptus (Eucalyptus robusta Smith) were used to produce plywood. The effects of sealing treatment and wood species on the formaldehyde emissions were studied. The anatomical characteris...

2001
Anthony H. Conner

Approximately 1 million metric tons of urea-formal-dehyde resin are produced annually. More than 70% of this urea-formaldehyde resin is used by the forest products in-*This information was written and prepared by a U.S. Government employee on official time and it is, therefore, in the public domain and not subject to copyright.

2010
Qi-Ning Sun Chung-Yun Hse Todd F. Shupe

Urea-formaldehyde resins modified by melamine were synthesized by four catalysts (H2SO4, HCl, H3PO4, and NaOH/NH4OH) with a F/U/M molar ratio of 1.38/1/0.074. Resin structure and thermal behavior were studied by C-NMR and DSC techniques. For H2SO4, HCl, and H3PO4 catalysts, resins were prepared by two stage pH adjustment: the first pH stage was set at 1.25 (H3PO4 pH 1.60) and second pH stage wa...

2013
An Mao El Barbary Hassan Moon G. Kim

A previous study of synthesizing low mole ratio urea–formaldehyde (UF) and urea–melamine–formaldehyde (UMF) resins, which included an acidic reaction step at the beginning of the typical resin synthesis procedure to obtain higher uron-type methylene–ether group contents, was repeated with the acidic reaction step extended to a higher viscosity. Compared to previous resins, the synthesized resin...

2010
Jeong-Hun Lee Sumin Kim

To discuss the reduction of formaldehyde and volatile organic compound (VOC) emissions from engineered flooring, cashew nut shell liquid (CNSL)-formaldehyde (CF) resin and CF/PVAc resin were applied for the maple face of the veneer bonding on plywood. The CF resin was used to replace urea-formaldehyde (UF) resin in the formaldehyde-based resin system in order to reduce formaldehyde and VOC emis...

2012
Wei Gao Jianzhang Li

Uron resin, a kind of urea-formaldehyde (UF) resin containing much more uron structure, were prepared. Several modi ed UF resins were obtained from mixing uron resins with normal UF resins as well as synthesizing UF resin with uron resin as raw material. is work demonstrated that the introducing of the uron structure reduced free formaldehyde content of UF resin and formaldehyde emission levels...

2010
James B. Wilson

Life-cycle inventory (LCI) data are needed to scientifically document the environmental performance of formaldehyde-based resins used in the manufacture of wood composite products. The resin data are needed by others to conduct LCI studies of wood composites when providing performance data for applications as governed by the many green building standards, purchasing guidelines, and energy and c...

Journal: :Revista de ciencias tecnológicas 2021

The objective of this study was the evaluation feasibility producing particleboard for general use using cotton gin waste generated in Argentina and urea formaldehyde resin. chemical composition size distribution particles ginning residue as well mechanical physical properties particleboards obtained were investigated. Density flexural strength produced with varying levels urea-formaldehyde res...

2013
Jizhi Zhang Xiaomei Wang Shifeng Zhang Qiang Gao Jianzhang Li

Three formaldehyde-based resins were prepared: urea-formaldehyde (UF) resin without melamine modifier (named UF0 resin) and melamineurea-formaldehyde (MUF) resins with melamine modifier added at two different synthesis stages (named MUF1 resin and MUF2 resin). The effects of the melamine addition stage on the performance and curing behavior of MUF resin were studied. Three-ply plywood bonded by...

2018
Freddy Muñoz Roger Moya

Physical and mechanical properties were evaluated on cross-laminated panels (plywood) fabricated with three plantation species (Cordia alliodora, Gmelina arborea and Vochysia ferruginea) from tropical climates in Costa Rica. The panels were glued with urea-formaldehyde resin modified with nanoclay at four concentrations (0,75; 1,00; 1,50 and 2,00 %) and unmodified resin. It was determined that ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید