2002 Fiscal Year Final Research Report Summary
Study on Chemical Decomposition and Repolymerization Process of FRP for Recycling
| Project/Area Number |
12450308
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
化学工学一般
|
|---|
| Research Institution | Tokyo Institute of Technology |
|---|
Principal Investigator |
TSUDA Ken Graduate School of Science and Engineering, Professor, 大学院・理工学研究科, 教授 (90016585)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SEMBOKUYA Hideki Graduate School of Science and Engineering, Assistant Professor, 大学院・理工学研究科, 助手 (70313343)
KUBOUCHI Masatoshi Graduate School of Science and Engineering, Associate Professor, 大学院・理工学研究科, 助教授 (00186446)
|
|---|
| Project Period (FY) |
2000 – 2002
|
| Keywords | Recycling / Plastics / Epoxy Resin / Nitric acid / Amine / Bisphenol / Chemical Recycling / Yield |
|---|
| Research Abstract |
Some kinds of epoxy resins prepolymer cured with some kinds of curing agents were prepared. They were chemically decomposed by nitric acid solution. The relation between the decomposed products and chemical structure of epoxy resin prepolymer and curing agents were investigated. Bisphenol F type epoxy resin cured with menthanediamine was the optimum combination in order to recycle epoxy resins. The epoxy resin was decomposed by 4 mol/1 nitric acid solution at 80 ℃ for 150 hours. Then decomposed product was extracted by ethyl acetate from the nitric acid solution. The decomposed product was added to the epoxy resin prepolymer at 25 wt% and cured with phthalic anhydride. The cured epoxy resin showed that the flexural strength was 1.5 times, the tensile strength was 4 times with respect to the epoxy resin containing no extract. The results of differential scanning calorimetry indicated the homogeneity of the chemical structure of the epoxy resin with extract. Thermal stability improved by
… More
adding extract because the glass transition temperature increased about 18℃. The results of chemical analysis suggested the possibility of the increase of the crosslink density due to the acceleration of curing reaction by amine group in the extract.
Glass fiber reinforced plastics were fabricated by using bisphenol F type epoxy resin cured with tetraglycidyldiaminodiphenylmethane (TGDDM) as a matrix resin. The FRP could be decomposed by similar method mentioned above. The decomposition time of matrix resin of FRP was almost the same as that of neat resin. The matrix resin completely disappeared and glass fiber could be recovered. The decomposed product was extracted from the nitric acid solution. The extract was added to prepolymer and cured with phthalic anhydride. The epoxy resin was well cured at the content of extract below 15wt% and the flexural strength increased. Three kinds of galss fiber were immersed in nitric acid solution. E-glass fiber as general purposes indicated that the fiber dissolved and the strength decreased remarkably. 0n the other hand, C-glass fiber as chemical purposes and T-glass fiber as mechanical purposes showed no significant degradation. It was suggested that C-and T-glass fiber could be recovered and reused as reinforcing fibers. Less
|
