| Summary: | 博士 === 國立臺灣大學 === 化學工程學研究所 === 105 === In this dissertation, three studies on novel polymers and their applications are reported. The first part is a new design for the rational design of poly (2,5-dihexyloxy-p-phenylene) (PPP) segments and poly (3-butylthiophene) (P3BT) conjugated block copolymer, which is synthesized and further used as a cooperative long distance ordered carrier transport network based on PC71BM bulk heterojunction (BHJ) hybrid system. The strong immiscibility from different backbone moieties and the large difference in crystallinity between the PPP and P3BT blocks allow this novel material spontaneously self-assemble into interpenetrating nanostructures, while forcing the PC71BM nanoparticles to be preferentially located in the amorphous PPP domain, rather than in the highly crystalline P3BT phase. The power conversion efficiency (PCE) of the PPP-P3BT/PC71BM device is 3.12 % and the homopolymer P3BT/PC71BM counterpart is 3.09 %. The further investigating results clearly demonstrate the advantages of fully conjugated block copolymers with different backbone moieties for generating preferential interface energy gradients and morphological sequences, thereby promoting a strong improvement in exciton dissociation and charge transport and enhance thermal stability, resulting in organic solar cell devices with the best performance and excellent long-term stability.
In the second part, several artificial model eyes developed to simulate the biomechanical response of human eyes with different material properties It is important to use IOP measurements to diagnose human eye health such as glaucoma. At present, the main method of estimating intraocular pressure is to apply pressure to the cornea and detect its deformation or force feedback. Poly(2-hydroxyethyl methacrylate) (PHEMA), poly(2-hydroxyethyl methacrylate-co-acrylic acid) (poly(HEMA-co-AA)) and the interpenetrating polymer networks (IPN) of Poly(ethylene glycol)/Poly(acrylic acid) (PEG/PAA) hydrogels were used as artificial corneal materials in this study. At the same time we tested the different corneal parameters for different intraocular pressure measurement instruments (Icare Tonometer, Schiøtz tonometer, Non-contact Tonometer(NCT)) in the measurement of intraocular pressure when the error range. Polyvinylchloride (PVC) thin film was induced to simulate the Bowman’s layer in actual human eye structure of cornea to perform the real situation of the human eye and reflect the IOP using Icare tonometer. In addition, PEG/PAA hydrogels have good mechanical properties, and water content and refractive index have the potential for future use as a biomaterial for clinical use.
In the third part, poly(ethylene glycol) (PEG) and poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (poloxamer407) crosslinked biocompatible macromers are synthesized for developing a novel porous artificial cornea skirt material. A series of P407-PEG hydrogels is produced from poly(ethylene glycol) diacrylate (PEGDA) and poloxamer407 diacrylate (P407DA) precursor solutions. Water and dichloromethane is used to induce polymer/solvent phase separation. The porosity and pore size distribution of P407-PEG hydrogels could be easily changed by tuning the ratio of P407DA and PEGDA in precursor solution. Highly porous cornea skirt materials can assist diffusion of water, nutrition and oxygen between skirt and stroma. Dynamic mechanical analysis and rheometer shows that compressive and shear storage moduli of all P407-PEG hydrogels fulfill in the strength range of human cornea (elastic modulus between 4 kPa and 40 kPa). P407-PEG hydrogels are implanted to Wistar rat thigh for 8 weeks to investigate biocompatibility of this artificial cornea skirt material. All rats have no obvious rejection or infection in whole implantation duration, and several compositions of P407- PEG hydrogels are demonstrate good biocompatibility. The data of swelling ratio, porosity, physical strength and paraffin processing subcutaneous implanted samples indicated that P407-PEG hydrogels are very potentially material of cornea skirt application.
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