Preparation And Properties Of Solvent Strippable Plastics

In this paper,a kind of strippable solvent plastic is developed,which is used to solve the problems of stripping membrane,high cost and strict requirement to environment of traditional anti-rust material.Without special requirement to the environment,this product is not only easy to strip,low-cost,but also has fine mechanical property and antiseptic property.Through measurement of the tensile strength,the specific elongation,the strippable and the leak tightness of the ethyl cellulose,the cellulose acetate,the perchloro-ethylene,the polystyrene,the polyvinyl-chloride and the chloroethylene-vinyl acetate,with recording and weighting points to evaluate their excellence,the ethyl cellulose is optimal,so the ethyl cellulose is selected as the filmogen.According to the principle of approximate solubility parameter,epoxy resin and dibutyl phthalate are chosen respectively as auxiliary filmogen and plasticizer.According to the adsorption theory,inhibitor is chosen.According to the principle of approximate solubility parameter,the filmogen,the auxiliary filmogen,the plasticizer can dissolve completely in the solvent is predicted.It will reduce the test times and improve the test efficiency by using the combination of the even experiment and the orthogonal testIn this paper,the tensile property experiment,the corrosive experiment,the rust resistance experiment,the electrochemical experiments are used to test the properties of solvent strippable plastics.They indicate the following points.The solvent strippable plastics have excellent tensile property,its tensile-strength reaches as high as 16.3MPa.The pure aluminum,the low-carbon steel and 316 type stainless steel have the good conformability. They have not appeared corrosion phenomenon 10 days later after the coating are coated on them.This coating has the excellent rust resistance.In salt spray test,the low-carbon steel and pure aluminum have not appeared any rust after having been placed respectively for 472h, 528h.They have not appeared corrosion phenomenon after being soaked separately in the running water for 480h,5%H₂SO₄ for 367h,5%NaOH for 486h and 3%Nacl for 402h.The coating has good corrosion resistance performance.Electrochemical experiments indicate: When coating Thickness is 20μm its free corrosion potential reaches - 0.164V which is obviously higher than that of bare steel(- 0.702V).The corrosion rate of coating is lower 4 magnitudes than that of bare piece in weak polarized area.The impedance value of the 30μm coating(R_po=6.89x10⁸/ohm-Cm²)is higher 6 magnitudes than that of bare chip under the same condition after being soaked in the 3.5%Nacl for 6 hours.According to the corresponding electrochemical impedance spectroscopy' Characteristics of coating system in the initial,middle and end stage of immersion,the physical models are established respectively.And then the EIS spectrum diagram of coating system in the corresponding immersion period is analyzed on the basis of different physical models,thus the corresponding parameters will be attained,so the performance of the coating will be evaluate quantificationally.The pH of the corrosion product in the cathode area and anode region is measured by using the far-ranging pH test paper,the corrosion reactions at the cathode and anode are analyzed.Then the corrosion mechanism of metal under coating is finally inferred.