Preparation And Properties Of Solid Epoxy Foam Composites

Solid epoxy foam materials have the excellent properties of epoxy resin and foam material,and are widely used in the fields of transportation,construction engineering,electronic filling and sealing materials,aerospace and Marine buoyancy materials.In order to improve the solid epoxy resin viscosity uncontrollable problem in the process of processing and large internal stress of epoxy resin after curing,low strength,poor toughness of defects,based on the solid epoxy resin as matrix,dicyandiamide as curing agent,4,4,double benzene sulfonyl-oxygen generation hydrazine(OBSH)as the foaming agent,was prepared by chemical foaming solid epoxy foam material,and its performance is studied,and the specific work is as follows:(1)With OBSH as the chemical foaming agent,the solid epoxy foaming material was prepared by two-step temperature-rising method.The temperature and time of pre-curing and the temperature and time of post-curing foaming steps were investigated by DSC and rotatory rheometer.Results show that the dosage of curing agent was 14%,the maximum level of epoxy resin curing cross-linking reaction,curing temperature is140 ?,the curing time of 110 min,foaming temperature and curing time after 180 ?respectively,and 20 min~30 min,cured completely under the condition of the preparation of foam material,combined with the result of SEM analysis,found that the bubble distribution and bubble hole size.At the same time,it was found that the two-step temperature-rising method improved the uncontrollable viscosity of the solid epoxy resin in the processing process to some extent,and the foaming property of the material was also improved.(2)Epoxy resin/GF foaming materials were prepared with solid epoxy resin and dicyandiamide as raw materials,chopped glass fiber was added,and chemical foaming agent was used to prepare epoxy resin/GF foaming material by two-step temperature rise method.It was found that the interfacial infiltration of GF with epoxy resin was the best when treated with amine coupling agent KH792 GF to join the epoxy resin/GF blend G? and eta are increased,that GF added to increase the viscosity of blend.Dynamic rheological results also showed that about 40 min at 140 ? can,system began to appear apparent viscosity rise,crosslinking curing effect in the system that became obvious that the addition of GF in a certain extent,improved the uncontrollability of solid epoxy resin viscosity.The results of SEM and mechanical properties test showed that when the GF content was 2 wt.%,the epoxy resin /GF foam material had the best foaming performance and mechanical properties.(3)By introducing A to initiate the cross-linking reaction of styrene-butadiene-styrene(SBS)to blend with epoxy resin,the epoxy resin/SBS foam material was prepared by one-step temperature-rising method through chemical foaming agent.The addition of SBS,the epoxy resin/SBS blend G? and eta are increased,A efficient to trigger the SBS system of crosslinking reaction can quickly increase ofviscosity,that do not require curing step,can be directly done by step up the preparation of epoxy resin/SBS foaming materials,greatly shorten the preparation time.The test results of SEM and mechanical properties showed that the epoxy resin /SBS foam material had the best foaming and mechanical properties when SBS was added in5 parts.