Study And Preparation Of Water-based Epoxy Modifying Acrylate Intumescent Finishing Fire Retardant Coating

Intumescent finishing fire-retardant coating is a new kind of coating which has both decorative and fire resistant function. recently, water-based finishing fire-retardant coatings become the focus of many researchers because of the laws and regulations about environmental protection in many countries. Although water-based coatings have perfect environmental friendliness, they have poor physical and chemical performances such as water resistance and adhesion performance. In addition, water-based fire-retardant coatings will product a lot of smoke which seriously hamper the application of fire-retardant coatings during the fire-retardant process, because they contain many polymers. Therefor, the study of intumescent finishing fire-retardant coating with high performance,low smoke and low toxicity is a main research direction in coating industry.Firstly, the water-based epoxy modifying acrylate latex is prepared by semi-continuous seeded emulsion polymerization and we have studied the effect of polymerization conditions on monomer final conversion rate. The results show that the best reaction condition is : initiator: 0.8%, emulsifier: 3%,SDS: OP-10 = 2:1,stirring speed:180rpm,seed latex:20%; we also find that there is a direct relationship between conversion and glass transition temperature of the latex film, the increase of final conversion rate provide a good controllability to the glass transition temperature of the latex film; In addition, the epoxy–acrylic latex prepared by the paper has low VOC,fast drying,good hardness,excellent water resistance and adhesion properties..We have prepared intumescent finishing fire-retardant coating and studied the effect of coating's fire retardant system,latex,filler and additives on fire-retardant performance. The results indicate that the coating has the best fire retardant performance when APP/PER/MEL weight ratio is 25/10/8 and latex content is 20%; TiO2 can enhance the intensity of intumescent carbon layer and improve the fire retardant performance, 7.5% is the best content; The introduction of EG can improve the fire-retardant performance obviously by improving the structure of the intumescent carbon layer and increaseing the carbon remains, 3% content of 80 mesh EG is the best content.The results of TG-DTG,SEM,XRD indicate that the thermal decomposition temperature of APP,PER,MEL and latex are consistent and they can match very well. TiP2O7 producted by TiO2 and APP under a high temperature plays an important role during the last step of the fire retardant process; Because of the surface adhesion and the intercross of cross-section, EG can enhance the intensity of the carbon layer and improve its structure, and then the fire retardant performance will be improved obviously.The effect of different smoke suppressant fillers on smoke and toxicity has been studied by CONE test. The results indicate that both ZB and LEE can reduce the release of the smoke and toxic gases obviously; Both of the two suppressant fillers mixed with EG can lead a further reduction on the parameters of smoke and toxicity, especially at the beginning of the fire retardant process. In a word, the release of smoke and toxic gases can be controlled at a low level in the fire retardant process.