【公開日：2024.07.25】【最終更新日：2024.04.16】
課題データ / Project Data
課題番号 / Project Issue Number
23NM0019
利用課題名 / Title
Biodegradable Materials
利用した実施機関 / Support Institute
物質・材料研究機構 / NIMS
機関外・機関内の利用 / External or Internal Use
外部利用/External Use
技術領域 / Technology Area
【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-
【重要技術領域 / Important Technology Area】（主 / Main）次世代ナノスケールマテリアル/Next-generation nanoscale materials（副 / Sub）-
キーワード / Keywords
enzymatic,hydrolysis,grafting, lipases,maleic anhydride, poly-epsilon-caprolactone
利用者と利用形態 / User and Support Type
利用者名（課題申請者）/ User Name (Project Applicant)
Thangunpai Kotchaporn
所属名 / Affiliation
筑波大学理工情報生命学術院
共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes
ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes
服部晋也
利用形態 / Support Type
（主 / Main）機器利用/Equipment Utilization（副 / Sub）-
利用した主な設備 / Equipment Used in This Project
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
We examined and compared the hydrolysis rates of PCL and PCL-g-MA using lipase PS in this work. PCL-g-MA hydrolysis was faster than PCL. The former could be totally hydrolyzed in 72 hours, but the latter needed 120 hours. For the first 48 hours, PCL-g-MA hydrolyzed at a faster rate than PCL. The presence of MA grafted onto PCL lowered crystallinity and prolonged the amorphous area, allowing lipase to diffuse into a PCL-g-MA rather than PCL. SEM examinations further revealed that the surface roughness and depth of the fractures increased with increasing hydrolysis time, and lipase hydrolysis created holes around the fractures. TGA, DSC, XRD, FTIR, and XPS analyses revealed that during lipase hydrolysis, the crystalline and amorphous portions of PCL and PCL-g-MA were largely damaged, transforming the crystal regions to amorphous regions. Furthermore, the crystallinity and hydrophilic characteristics of the lipase hydrolysis reaction were validated by POM imaging and CA measurements. Because of the nucleation effect, the size of PCL and PCL-g-MA spherulites was reduced after lipase hydrolysis. All of the results indicated that MA grafted onto PCL would be one of the acerated materials that might hydrolyze in the natural environment. This method is expected to produce cost-effective and ecologically beneficial PCL-based composites (such as plastics and fibers) when mixed with other natural eco-friendly ingredients such as cellulose and lignin.
実験 / Experimental
Gel Permeation Chromatography (GPC) The number average (Mn), weight average (Mw), and polydispersity index (PDI) of the PCL and PCL-g-MA before and after lipase hydrolysis were determined using GPC (GPC101, Shodex, Japan) with a Shodex refractive index detector (RI-71S). All samples were prepared and dissolved in THF with a stabilizer (1.0 mg mL−1), filtered through a PTTF filter (0.45 µm), flushed through a Shodex KF-806L column at 0.8 mL min−1 in the mobile phase of THF with a stabilizer and calibrated using the standard Poly (methyl methacrylate): PMMA.
結果と考察 / Results and Discussion
Mw, Mn, and PDI values for PCL and PCL-g-MA via GPC are shown in Table 1. The results showed that after grafting MA onto the PCL, Mw reduced and the dispersion broadened. According to the theory, three distinct reactions might occur during the grafting process: i) MA grafting onto the PCL backbone, ii) PCL crosslinking, and iii) acid-catalyzed degradation of the polyester via MA. The main cause of the decrease in Mw and increase in PDI should be acid-catalyzed degradation of the original PCL, resulting in the synthesized PCL-g-MA with a short chain length.
図・表・数式 / Figures, Tables and Equations
Table 1. Mw, Mn, and PDI of PCL and PCL-g-MA
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
成果発表・成果利用 / Publication and Patents
論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)
-
Kotchaporn Thangunpai, Effects of Grafting Maleic Anhydride onto Poly‐ɛ‐caprolactone on Facilitative Enzymatic Hydrolysis, Macromolecular Materials and Engineering, 308, (2023).
DOI: https://doi.org/10.1002/mame.202300067
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
特許 / Patents
特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件