Studies On Preparation And Toughening Of Phenolic Resin Foam

In this thesis, formaldehyde and phenol was synthesized to phenolic resin, and thus prepared the phenolic resin foam insulation. Synthesis conditions and influencing factors of the resol phenolic resin foam performance were studied and approached in this paper aim to find out the optimum condition and process of the synthesis of phenolic resin also this is One of the key problems that would be solved in this experiment.Based on the synthesis of the high combination property formaldehyde phenolic resin, research of foaming dispensation was conducted, and then Better over-all performance phenolic resin foam was prepared, Meanwhile, the thermal stability of phenolic foam was analyzed.In the study of the phenolic resin synthesis process, the reaction F/P molar ratio was discussed accompanied with the discussion of the influence that reaction temperature and reaction time have on the phenolic resin composition and the residual free formaldehyde and free phenol. Meanwhile, the relationship of resin viscosity changing with the reaction conditions was analyzed by using digital viscometer. The study indicates that reaction molar ratio and reaction time are primary factors that influence the resin property such as viscosity, free aldehyde and free phenol. In addition, the effect that resin viscosity has on foam properties was analyzed also the resin indicators with better manipuility and foam overall performance was indicated.This experiment found out the results as follows:the viscosity of the phenolic resin foam needs to be controlled at3000-5000cp. Determine the response of the F/P molar ratio of1.7:1, the reaction temperature of90℃, reaction time of1.5h.The synthetic resin was prepared to phenolic resin foam conducting the study of the effect that resin had on foam.In determining the resin viscosity, the research of how the foaming temperaturethe blister, the solidified agent influent the properties of foam was conducted. The results indicate that:the temperature increment is conducive to foaming, and foam perforation occurred as the temperature growed too high. When controlling the foaming temperature at55℃～65℃, the bubble foaming time shortening as the amount of solidified agent increasing, ultimately tothe amount of10%～16%, especially13%finalized, good quality foam formed with little apparent density change. Three kinds of plasticizer(polyethylene glycol, polyvinyl alcohol, boric acid ammonium fluoride) was respectively selected to modify the resin, testing the mechanical property and compression strength of the phenolic foam after and before the modification using a universal material testing machine to, study the toughening effect, water absorption, apparent density, free aldehyde, free phenol and foam structure, while using TG-DTA analyzer testing the stability of phenolic resin, finally discovery polyethylene glycol has the best toughening effect among these plasticizes. Compressive strength of this phenolic foam is0.062～0.481Mpa measured by a universal material testing machine.