Preparation And Research Of New Type Of Green Environmental Protection Particleboard

Particleboard is a wood based panel composite manufactured by compressing small wood particles while simultaneously bonding them with an adhesive.With the growing worldwide shortage of wood resources,utilization of wood particles,sawmill shavings,flakes,or even sawdust together to produce particleboard has become one of the main way to solve the contradiction between supply and demand of timber.Nowadays,particleboard is used not in products such as furniture,desks and floor,but in construction,shipbuilding and other fields.The adhesive manufacturing particleboard has experienced from the natural polymer adhesives to the synthetic adhesives.Urea-formaldehyde(UF)resin is the primary binder of interior-grade wood composite boards at present,such as particleboard,medium-density fiberboard,and plywood.Urea-formaldehyde resin is widely used in particleboard due to its short press time,low cost,excellent adhesion,intrinsic cohesion,high reactivity and water solubility,and lack of color in the finished product.However,there is formaldehyde released when Urea-formaldehyde resin has been used.Formaldehyde can exert a series of negative effects on people's physical and mental health,it is considered a priority pollutant in public.With the improvement of people's living conditions,people's requirement of environmental protection is higher and higher.The urea-formaldehyde resin has been begun to gradually narrow the scope of its application.One current challenge is to reduce or eliminate the relatively high formaldehyde emission levels of boards that arise due to the urea-formaldehyde resin.Researches have been focused in reducing the emissions or exposure to formaldehyde by adding scavengers,using alternate fossil fuel based-resins without formaldehyde or by using binders based on renewable materials like those based on soy flour are becoming more and more important.Environmental protection adhesives have been used to manufacture particleboards without formaldehyde release in this paper.The particleboards are friendly to the environment.Formaldehyde emission of the particleboardhave released only from lumber itself,which is suitable for the needs of social development of wood based panel.The thesis was divided into three parts.In the first part,epoxy resin curing agent has been obtained by 2-(2-Aminoethylamino)ethanol modified epoxy soybean oil.Then the epoxy resin curing agent and epoxy resin were used as adhesive to manufacture particleboards.Mechanical and physical properties of particleboard made from epoxy resin and hardener were characterized.The results show that the particleboards have good density on modulus of rupture(MOR),modulus of elasticity(MOE),internal bonding(IB)and other properties.The properties can meet the Chinese National GB/T 4897-2003 standard requirements.In the second part,a type of plant oil base polyamide was used as hot melt adhesive to manufacture particleboards.The polyamide hot melt adhesive can be melted under certain temperature,and solidify rapidly after cooling.The particleboards with polyamide hot melt adhesive not only have good mechanical properties such as density on modulus of rupture(MOR),modulus of elasticity(MOE),internal bonding(IB),but have the characteristic of repeated suppression.So this type of particleboard can avoid secondary waste of resources,and improve the efficiency of resources use.In the third part,the particleboards were manufactured by plant oil base polyamide mixed with soy protein.The properties of particleboards which made with pure plant oil base polyamide are lacking sometimes.So using soy protein and plant oil base polyamide blend to suppress particleboards has been thought out,which can improve the properties such us density on modulus of rupture(MOR),modulus of elasticity(MOE),internal bonding(IB).The particleboards manufactured by plant oil base polyamide mixed with soy protein can conform to the higher requirement for use.