The Preparation And Property Researches Of Flame-retardant Liquid Silicone Rubber Foam Material

Liquid silicone rubber foam materials is a kind of new developed flexible porous polymer elastomer,which has the advantages of non-toxic,environmental protection,vibration damping,sound insulation and heat insulation performance,no by-products vulcanization process,easy processing,convenient molding,etc.It has been widely used in the military and civilian areas,however,nowadays,liquid silicone rubber foam materials cannot be produced on a large scale due to the preparation of mold and process limitations.Therefore,it has a promising prospect for industrial continuous production process.Other,liquid silicone rubber has been used as a basic material,flame retardant and foaming have been synergistically studied to prepare liquid silicone rubber fire-retardant foam material(LSRFRFM).There are few researches in this field at home and abroad.The market is blank,so the preparation of liquid silicone rubber flame retardant foam material,the flame retardant and foaming collaborative research,and study the formula and technology,which are very research significanc.In this thesis,the molding liquid silicone rubber with addition of foaming agent and flame retardant has been used.Hydrogen-containing silicone oil has been used as a cross-linking agent.Under the platinum catalysis,Fine formulation and industrial continuous production process.has been explored to prepare high-performance liquid silicone rubber flame-retardant foams,and characterized by surface morphology and compared with the physical,mechanical,and flame-retardant properties.Three kinds of preparation techniques of LSRFRFM were explored.The first is a chloroplatinic acid catalyst system:the vulcanization temperature is 180 ℃.and the vulcanization time is 30 min;The second is ethanol dilution platinum-catalyst(AL-PC)catalyst system:the curing temperature is 160 ℃ and the vulcanization time is 30 min.The third type is a vsd-PC catalytic system:the vulcanization temperature is 120 ℃ and the vulcanization time is 15 minutes.Both the AL-PC catalytic system and the VSO-PC catalytic system can be used as a industrial continuous production process.Through the comparison of the physical,mechanical and flame retardant properties of the flame retardant gradient experimental products of the AL-PC catalyst system and the VSO-PC catalyst system,it has been known that the LSRFRFM products of the AL-PC catalyst system are generally medium-foamed materials,and the apparent density average is 0.372 g/cm3.The LSRFRFM products of the VSO-PC catalytic system are generally low foaming materials,and the apparent density is 0.563g/cm3;the mechanical properties and flame retardancy of VSO-PC catalyst system products are higher than that of AL-PC catalyst system products.The tensile strength of VSO-PC catalyst system products is 64.3%higher than that of AL-PC catalyst system,and the elongation at break increases by an average of 17.3%,Smoke density rating(SDR)all can achieve B1 level building smoke density standard,standard products are more likely to achieve flame retardant material,namely building B1 level oxygen index standard,and burning after the formation of the carbon layer pore become smaller,more compact,basic is stratified.Flame retardant gradient experiment through two kinds of technology products comprehensive performance comparison,select the optimal industrial VSO-PC catalytic system for continuous production process,this process of foaming agent gradient experiment,the effects of foaming agent content on LSRFRFM products,determine the optimal process can make the LSRFRFM products under the best comprehensive properties of foaming agent the best addition amount,the results show that when the product microspheres foaming rate matches the vulcanization rate,the product foaming effect is the best,the product cell is uniform and dense,and based on the comprehensive analysis of the performance of the product,When the adding amount of foaming agent is 1.5 g,the overall performance is optimal,the apparent density is 0.512 g/cm,the porosity is 51.7%,the Shore O hardness is 39.7 HO,the falling rebound rate is 56.6%,the tensile strength is 0.6 MPa,and the elongation at break was 386.1%,OI 25.7%,SDR 32.24%,and MSD 48.07%.