there are adequate sources for wood adhesives, but scarcity of oil resources can affect the cost and future availability of oil based resins. for avoiding of this process, seeking for feasibility of replacement of these oil feedstocks is necessary. in present work, thermal behavior of urea formaldehyde resin modified by furfural was investigated. the thermo-gravimetry was used for this purpose,...

A powdery product was obtained by the reaction of methylolated melamine with alkyl resorcinols to form melamine-bridged alkyl resorcinols (MARs). The effects of the addition of this powder on the bonding strength and formaldehyde emission of urea–formaldehyde (UF) resins were investigated. Three types of UF resins with a formaldehyde/urea molar ratio of 1.3 synthesized by condensation at pH 1.0...

For the development of a cost-effective melamine-modified urea formaldehyde resin (MUF), the study evaluated the effects of reaction pH and melamine content on resin properties and bond performance of the MUF resin adhesive systems. Eight resins, each with three replicates, were prepared in a factorial experiment that included two formulation variables: two reaction pHs (i.e., 4.5 and 8.0) and ...

partial replacement of formaldehyde with furfural in the urea-formaldehyde resin on the formaldehydeemission, physical and mechanical properties of particleboard was investigated. the modulus ofrupture (mor), modulus of elasticity (moe), internal bond (ib), water absorption (wa), thicknessswelling (ts) and formaldehyde emission (fe) of poplar particleboards made with the modifiedresins were mea...

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.

MO XF, FAN DB, QIN TF & CHU FX. 2015. Curing characteristics and adhesion performance of phenol–formaldehyde resins with composite additives. The curing characteristics of cure-accelerated phenol–formaldehyde resins with composite additives were investigated by differential scanning calorimetry analysis and gelation test. The pot lives and adhesion performances of phenol–formaldehyde resins wer...

This paper reports a comparison of adhesion behavior urea-formaldehyde (UF) with those melamine-urea-formaldehyde (MU) resins in bonding wood by analyzing the results published literatures. For this purpose, UF prepared blending low-viscosity resin (LVR) high-viscosity (HVR) at five different and two formaldehyde/urea (F/U) molar ratios (1.0 1.2) was compared MUF synthesized either simultaneous...

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...

To upgrade the performance of urea-formaldehyde (UF) resin bonded particleboards, melamine modified urea-formaldehyde (MUF) resins based on strong acidic pH catalyzed UF polymers were investigated. The study was conducted in a series of two experiments: 1) formulation of MUF resins based on a UF polymer catalyzed with strong acidic pH and 2) determination of the effects of increased melamine co...

Maritime pine (Pinus pinaster) sawdust was used to produce liquefied wood by the polyhydric method with acid catalysis. The process was optimized to produce the highest amount of liquefied wood. Wood liquefied at 160oC for 90 min was used in the adhesion tests. The bond strength of veneer glued with ureaformaldehyde and melamine-urea-formaldehyde resins and several mixtures of liquefied wood wi...