Development of Biodegradable Semipermeable Membranes using Non-solvent induced phase separation, Thermally induced phase separation, and Cross-linking of Surface Immobilized Poly(ethylene glycol)
비용매 유도 상분리, 열 유도 상분리 및 교차결합을 이용하여 표면에 폴리에틸렌 글리콜을 고정한 생분해성 반투과막 개발
- 주제(키워드) Semipermeable Membranes , Polycaprolactone(PCL) , Thermally Induced Phase Separation , Nonsolvent Phase Separation , Surface Treatment
- 발행기관 고려대학교 대학원
- 지도교수 이규백
- 발행년도 2024
- 학위수여년월 2024. 2
- 학위명 석사
- 학과 대학원 바이오의공학과
- 원문페이지 54 p
- 실제URI http://www.dcollection.net/handler/korea/000000279518
- UCI I804:11009-000000279518
- DOI 10.23186/korea.000000279518.11009.0000387
- 본문언어 영어
초록/요약
This paper focuses on research into the development of semipermeable membranes based on Polycaprolactone (PCL). In particular, this study extensively investigates the precise fabrication of semipermeable membranes using principles of Thermal Induced Phase Separation (TIPS) and Nonsolvent Induced Phase Separation (NIPS), aiming to achieve delicately control over membrane characteristics such as porosity and pore size. Our research has demonstrated a distinct correlation between the good solvent/bad solvent ratios and the morphological attributes like pore size and porosity of the semipermeable membranes, as evidenced by Scanning Electron Microscopy (SEM) analyses. Furthermore, additional surface treatment processes were employed, where the Humidity assisted photochemical hydroxylation (HaPHy) technique significantly enhanced the hydrophilicity of the membranes, confirmed through contact angle measurements. Moreover, the application of Hexamethylene diisocyanate (HMDI) and 4-arm Polyethylene glycol (PEG) in further functional surface treatment processes allowed for the modulation of porosity and pore sizes of the membranes. The outcomes of each surface treatment were substantiated through ATR-FTIR spectroscopy measurements. The sucrose diffusion experiments were conducted to assess the selective permeability of the membranes, revealing that membranes fabricated with higher solvent concentrations exhibited increased sucrose diffusion. This was corroborated by the experimental results obtained using a diffusion cell. Particularly, the sucrose diffusion experiments with surface-treated semipermeable membranes showed a significant decrease in sucrose permeation, proving that the limitations associated with conventional fabrication methods of semipermeable membranes can be resolved through functional surface treatments. This study presents innovative methods for overcoming the limitations in performance and stability of traditional semipermeable membranes through temperature and solvent miscibility control, and advanced surface treatment technology. Furthermore, by demonstrating that the limitations related to the conventional fabrication methods of semipermeable membranes can be addressed through functional surface treatments, this research is expected to contribute significantly to the advancement of various fields, including medical, environmental engineering, and chemical applications in areas such as fuel cells.
more초록/요약
본 논문은 PCL(Polycaprolactone) 기반의 반투과막의 개발에 관한 연구이다. 특히, 해당 연구에서는 다공성 및 기공 크기와 같은 막 특성에 대한 정밀한 제어를 달성하기 위해 TIPS(Thermal Guided Phase Separation) 및 NIPS(Nonsolvent Guided Phase Separation) 원리를 사용하여 정밀한 반투막 제작 방법을 주로 탐구하였다. 우리의 연구에서는 잘 녹는 용매/잘 녹지 않는 용매 질량 비율과 반투과막의 기공 크기 및 다공성과 같은 형상학적 상관관계를 주사 전자 현미경(SEM) 분석을 통해 증명하였다. 또한, 추가적인 표면처리 과정에서 표면처리 기술로써 Humidity assisted photochemical hydroxylation (HaPHy)를 통해 membrane 의 친수성이 매우 향상된 것을 contact angle 을 통해 확인할 수 있었다. 그리고, 추가적인 기능성 표면처리 과정에서 HMDI(Hexamethylene diisocyanate)및 4-arm Polyethylene glycol(PEG)을 적용하여 membrane 의 다공성과 기공의 크기를 조절할 수 있었고 표면처리가 진행된 결과는 각 표면처리 과정별로 ATR-FTIR spectroscopy 측정을 통해 증명하였다. 최종적으로 반투과막의 선택적 투과성을 평가하기 위해 Sucrose를 이용한 확산 실험이 수행되었으며 높은 용매 비율로 제작된 반투과의 경우 Sucrose 확산이 증가한다는 사실을 diffusion cell 을 이용한 본 연구의 실험 결과를 통해 확인할 수 있었다. 특히, Sucrose 를 이용한 확산 실험에서 표면처리를 진행한 반투과막에서 Sucrose 의 투과율이 크게 감소하는 결과를 통해 기존의 반투과막의 미세 기공 조절과 관련된 한계점을 기능성 표면처리를 통해 해결할 수 있다는 것을 증명하였다. 본 연구는 온도와 용매의 혼화성, 새로운 표면처리 기술을 통해 기존의 반투막의 성능 및 안정성에 대한 한계점을 개선할 수 있는 혁신적인 방법을 제시하였다. 또한, 기존의 반투과막의 미세 기공 조절과 관련된 한계점을 기능성 표면처리를 통해 해결할 수 있다는 사실을 증명함으로써 의료, 환경공학, 연료 전지와 같은 화학 응용 분야와 같이 다양한 분야의 발전에 기여할 것으로 기대된다.
more목차
TABLE OF CONTENTS
ABSTRACT ...........................................................................................................................i
국문 초록 ............................................................................................................................iii
ACKNOWLEDMENTS........................................................................................................v
TABLE OF CONTENTS .....................................................................................................vi
LIST OF FIGURES............................................................................................................viii
CHAPTER 1. INTRODUCTION..........................................................................................1
CHAPTER 2. Theory and Thesis..........................................................................................3
2.1 Polycaprolactone .....................................................................................................3
2.2 Thermally induced phase separation (TIPS)............................................................3
2.3 Nonsolvent induced phase separation (NIPS) .........................................................8
2.4 Surface treatment using Photocatalysis.................................................................12
CHAPTER 3. Material and Method ....................................................................................15
3.1 Fabrication of semipermeable membrane via phase separation ............................15
3.2 Sucrose diffusion through semipermeable membranes.........................................15
3.3 HaPHy surface treatment of semipermeable membranes......................................17
3.4 Surface modification with Hexamethylene diisocyanate (HMDI) ........................18
3.5 Cross-linking with surface immobilized 4-arm Polyethylene glycol (PEG).........18
CHAPTER 4. Results..........................................................................................................20
4.1 Analyzing the morphology of semipermeable membranes based on good solvent
and bad solvent concentrations....................................................................................20
4.2 Diffusion test of semipermeable membranes produced via NIPS and TIPS .........24
4.3 Results of surface treatment on semipermeable membranes.................................26
4.3.1 HaPHy surface treatment................................................................................26
4.3.2 Surface modified using Hexamethylene diisocyanate (HMDI)......................27
vii
4.3.3 Cross-linking with surface immobilized 4-arm Polyethylene glycol (PEG)..28
4.4 Results of surface treatment on semipermeable membranes.................................29
4.5 Diffusion test of surface treatment on semipermeable membranes.......................32
CHAPTER 5. CONCLUSION ............................................................................................34
REFERENCES....................................................................................................................36
