Synthesis And Modification Of Environmentally Friendly Sucrose-urea Adhesive

At present,man-made board is mainly used in the industrial adhesives urea-formaldehyde resin,phenolic resin,melamine and formaldehyde resin adhesives,people commonly known as the "three formaldehyde adhesive",because the synthesis of formaldehyde is one of the main raw material,the reaction is not fully in the process of reaction of formaldehyde,melamine formaldehyde resin in use process affected by light,heat,oxygen and other role will release such as formaldehyde.As long as the use of melamine formaldehyde resin can not fundamentally solve the problem of formaldehyde pollution.With the development of the society,the awareness of green environmental protection strengthen ceaselessly,in the face of wood industry and the rapid development of the dwindling fossil resources present situation,seek fundamentally eliminate or reduce the formaldehyde pollution to the environment,development of green environmental protection,renewable resources as raw materials,wood adhesives to achieve the coordinated and harmonious development of human and the natural environment,walking the road of sustainable development,is the adhesive industry research and development,production and application in the field of colleagues and common concern problem to be solved.This thesis mainly studies using sucrose instead of formaldehyde and urea,respectively,under the condition of acidic and alkaline polycondensation reaction synthesis of biodegradable,green environmental protection adhesives,and explores the sucrose and urea were synthesized under the condition of alkaline reaction principle.The reaction of sucrose with urea were synthesized under the condition of alkaline and acidic conditions also is same,have passed 5-hydroxy methyl-2-furfural(HMF)the intermediate process.By physical blending modification methods of its water resistance is improved.Under the condition of acid added xanthan gum and sodium carboxymethyl cellulose(CMC)to enhance the water resistant performance,in alkaline conditions to add animal protein and vegetable protein increase its water resistance.Bonding strength as the evaluation standard of the reaction conditions by single factor and response surface analysis method for optimizing.Synthesis of sucrose-urea,sucrose-urea-xanthan gum,sucrose-urea-CMC,sucrose-urea-xanthan gum-CMC,sucrose-urea-soy protein,sucrose-urea-soybean meal,sucrose-urea-cotton meal,sucrose-urea-fish meal,sucrose-urea-feather meal 9 kinds of adhesive.By infrared(IR),gel permeation chromatography(GPC),thermogravimetric(TG)characterization of its structure.The green environmental protection adhesives bonding strength and water resistance are improved.Add protein alkaline conditions of green environmental protection adhesives bonding strength near the traditional urea formaldehyde resin adhesive strength,under the condition of acid synthesis of adhesive bonding strength of adhesion agent and traditional urea formaldehyde resin adhesive strength and distance.Synthesis of the water resistant performance of green environmental protection adhesives and the traditional water resistance of urea-formaldehyde resin and large gap,have some room for improvement.Using sucrose as raw material instead of formaldehyde,fundamentally solved the pollution problem of formaldehyde,the synthetic adhesives raw material price is low,save the cost,and raw materials belong to renewable resources,in accordance with sustainable development thought.This paper synthesized has good development prospect of green environmental protection adhesives.