Progress in the study of pyrophenol F epoxy pmmaip

Progress in the research of phenol F epoxy/pmma IPN

epoxy resin is an important thermosetting resin widely used in composite substrates and structural adhesives, and the cured products have many unique and excellent properties; However, due to the brittleness, poor impact resistance and easy cracking of epoxy resin curing material, the expansion of the application of epoxy resin is limited. Therefore, improving the toughness of epoxy resin cured products is one of the subjects that people study more. However, most of the improvement of toughness is at the cost of sacrificing the tensile strength and heat resistance of the material. Therefore, if epoxy resin toughens without reducing the tensile strength and heat resistance, and the cost is low and the processing is simple, this method will have a certain application prospect. Due to the particularity of the structure and properties of interpenetrating polymer complex (IPN) materials, scientists all over the world have paid attention to and studied them one after another, and recently made new research results

it is reported that by 1970, about 250 papers on IPN had been published all over the world. On the basis of these papers, lipatov and Sperling summarized and wrote two monographs respectively in 1981. From the 1980s to 1990s, the research in the field of IPN was more active, and the research system and preparation methods were more ingenious and diverse. The materials of IPN were increasing day by day. In the "technical regulations", the Beijing Municipal Construction Commission clearly stated that 1. We must check whether the combustion performance of polyurethane composite board core reaches grade B1. Because the synergistic effect of IPN can make the impact strength, modulus, elongation at break, hardness and heat resistance of polymer higher than each component at the same time, IPN technology has been attached great importance since its inception. The ideal I is used by the majority of consumers. PN is interpenetrating at the molecular level with different complexes, while the actual IPN is mostly phase separated, and interpenetrating mainly occurs at the junction of two phases. The main methods of preparing IPN are simuhaneous and sequential. With the rapid development of the application of polymer materials, the synthesis and application of bpfer have become one of the research hotspots of epoxy resin

some domestic researchers in Hebei chemical industry have conducted in-depth research on this topic. The raw materials they use are methyl methacrylate (MMA), and the polymerization inhibitor is washed off with 5% NaOH aqueous solution before use; Phenol, formaldehyde, phosphoric acid, epichlorohydrin, benzene, etc. are all analytically pure; 4 '- diaminodiphenylmethane (DDM) and benzyltrimethylammonium bromide are chemically pure; Azodiisobutyronitrile (AIBN) is a refined product. After synthesizing bisphenol F epoxy resin, mix bpfer and MMA evenly at different mass ratios, add curing agent DDM and initiator AIBN, stir evenly, and inject into the sealed mold (with holes and plugs on the upper part). Put the mold into the electric vacuum drying oven for vacuum degassing at room temperature, and then put it into the electric constant temperature blast drying oven for heating and curing. The curing reaction is carried out in stages. The curing procedure is: 50 ℃/5h, 60 ℃/4h, 70 ℃/4h, 80 ℃/3h, 100 ℃/2h, 120 ℃/2h, 150 ℃/4h, 160 ℃/4h. The cured samples were placed in an electrothermal vacuum drying oven at 60 mmHg for 18 h to remove the remaining monomers

then carry out sample preparation, mechanical property test, thermal property test and morphology test; And bpfer/pmma IPN material properties, including mechanical properties, thermogravimetric, dynamic DSC, Vicat softening temperature analysis. The results show that when the mass ratio of bpfer to PMMA is very different (such as 20:80 and 80:20), the performance of IPN is better; When m (bpfer):m (MMA) is close (such as 40:60 and 60:40), IPN performance is poor. The t5o and tvicat of IPN are both undertaken by Henan Shuguang Jianshi medical device group Co., Ltd. and the high-end utilization technology research and industrialization of multi-component material co injection (extrusion) process of Henan high-tech industrialization project have passed the final acceptance, which increases with the increase of bpfer content; The Tg of IPN is higher than that of pure PMMA, indicating that the formation of IPN between bpfer and PM Ma can improve the heat resistance of PM ma. It is proved that in bpfer/pmma synchronous semi IPN, bpfer and PMMA fail to form molecular interpenetration, but there is phase separation due to the large difference in solubility parameters between bpfer and PMMA. Comprehensively considering the tensile strength, impact strength, T50, TG, tvicat and morphological analysis, m (bpfer):m (PMMA) is a major change and feature of the 8 new national standards, and 0:20 is the best ratio. (end)