Adhesive is the key that the object that uses for the main industry such as the sources of energy, building and car creates light simple structure. However, current adhesive has a common problem: Dismountable and can repeat use adhesive to be done not have mostly very good agglutinant; Exceeding agglutinant adhesive is not reversible. Development reversibility adhesive can make full use of its can reclaim gender and but durative, because this is in,the domain such as electron and medicine has very great sense. However, the strong cross-linking network that strong agglutinant need secures, and the exercise that reversibility adhesive needs to rely on dynamic catenary. What move as a result of strong cross-linking network and dynamic catenary is mutual and repellent, two respects that satisfy adhesive very hard at the same time - high-powered with reversibility.
Recently, filip E of Belgian Ghent university. The agent of dynamic polyamide solidify that Du Prez taught task group to develop two kinds to be used at epoxy resin sclerosis, synthesized adhesive of a kind of new dynamic epoxy resin, in keep fast take off stick ability while, the use temperature that raised adhesive significantly (> 180oC) . This adhesive can be sparked below high temperature, maintain agglutinate inside very wide temperature range at the same time, to the relevant temperature window on industry, the height that is technologies of pair of existing adhesive colophony is compensatory. This job with “Epoxy Adhesives With Reversible Hardeners: Co
Ntrollable Thermal Debo
Nding In Bulk And At Interfaces” is published on Advanced Materials for the problem. Researcher discovery, polyamide framework can be passed cricoid inferior the formation of amine undertakes be heatinged up reversibly sticking, and do not need activator or additive (graph 1) . With well-known furan - Ma Lai acyl inferior amine system and other substantially weaker key photograph is compared, of polyamide take off stick be in only the change is adopted below higher temperature apparently amine of 2 armour acyl and cricoid inferior between amine balance and happen. Researcher passes pair of amber acid 2 armour ester or the fifth of the ten Heavenly Stem 2 acid the simple processing of 2 armour ester, preparation agent of solidify of two kinds of dynamic epoxy resin, get together namely amber acyl amine (PSA) and get together the fifth of the ten Heavenly Stem 2 acyl amine (PGA) , use technology of conventional epoxy resin solidify, preparation applicable the epoxy resin adhesive at all sorts of surface interfaces (graph 2) . In process of epoxy resin solidify, cricoid inferior priming paint of alkyl of amine radical silicon is applied at the surface, reversible acyl amine key can be formed on the interface.
Graph 1. The design strategy of adhesive of reversible annulus oxygen
Graph 2. Phase of data of polyamide of oxygen radical trends compares the blame annulus of sketch map of craft of epoxy resin solidify and report, makings of base material of dynamic annulus oxygen shows apparent thermal stability, can undertake compression shaping below 250 ℃ . In addition, when using agent of dynamic polyamide solidify, can come true to arrive to transfer of tenacity apparently from brittleness, tenacity is highest increased 10 times, and modular volume dropped only 10% , this shows it is OK that dynamic polyamide introduces to bolt in epoxy resin improve mechanical performance effectively (graph 3) .
Graph 3. Of the function of dynamic epoxy resin and traditional epoxy resin build receive shear strength (make an appointment with 4MPa) photograph comparing, of dynamic epoxy resin build receive shear strength (make an appointment with 7MPa) increased about 2 times, because strong hydrogen key was formed between key of dynamic acyl amine and base material surface,this is, increased conglutinate power thereby. In the meantime, these dynamic epoxy resin can repeat for many times as adhesive use, its agglutinate function can maintain 90% to 95% (graph 4) .
Graph 4. Stick receive alkyl of intensity silicon oxygen to often be used to modified expresses an interface, the surface after silicon alkyl modified is OK with uncle amine (be similar to epoxy resin) produce open loop reaction, this also can realize reversible agglutinate (graph 5) . The surface of modified of all silicon alkyl is in on besmear after adhesive of dynamic epoxy resin, also show the clear improvement of adhesiveness, its interface bonding strength can increase 7MPa from 4MPa, increased nearly double. Again agglutinate experiment (heat namely 200°C, 2 minutes cool gradually) make clear, layer of thin dynamic silicon alkyl can make of the surface stick again receive intensity to restore original 90% to 95% , this shows interfacial interaction sticks attached middle school to also having main effect in systematic whole (graph 6) .
Graph 5. Silicon alkyl modified surface
Graph 6. Of surface of silicon alkyl modified stick receive intensity verdict: Researcher developed a kind solid and the data of dynamic epoxy resin that uses easily, can use as have the dynamic adhesive that can accuse to stick. Compare with the epoxy resin photograph of amine solidify, material of this kind of dynamic epoxy resin shows advantageous heat and mechanical performance. This research conduces to development not only new-style, the epoxy resin material related to industry, and also be adhesive take off stuck a mechanism to offer new view.
