Composition of epoxy-resin photopolymer with enhanced photosensitivity

본 발명은 광 기록 가능한 단량체를 함유하는 에폭시 수지형 가교 매트릭스 시스템에 기반을 둔 고용량 홀로그래픽 저장 매체의 광고분자에 관한 것으로, 보다 상세하게는 에폭시 수지 전구체로 거대 단량체(macromer) 도입을 통해 매트릭스의 가교 밀도 감소를 유도하여 향상된 광민감도 및 높은 회절효율을 갖는 에폭시 수지형 광고분자 조성물에 관한 것이다. 본 발명의 광고분자는 광학적 품질이 우수하고 치수 안정성을 갖는 에폭시 수지의 가교 매트릭스 도입을 통해 광산란 손실과 부피 수축이 적고 동시에 높은 회절 효율과 향상된 광민감도를 갖는 새로운 광고분자를 제공하는 데 있다. 본 발명에 의해 제조되는 에폭시 수지형 광고분자는 우수한 상안정성과 낮은 부피 수축을 가지므로, 저장된 데이터를 재생시킬 수 있는 신뢰성(fidelity)를 보장할 수 있으며, 높은 회절 효율과 향상된 광민감도를 통해 정보 저장의 기록 속도가 뛰어난 고용량 홀로그래픽 정보 저장 매체로의 응용이 가능하다

High photosensitive photopolymers via introducing the photopolymerizable molecular-sized inorganic units

본 발명은 광반응성을 갖는 분자 크기의 무기물을 함유하는 광고분자를 제조하는 데 있다. 고분자 매트릭스로 폴리메틸메타크릴레이트와 광중합 가능한 단량체로 비닐카바졸을 무기물, 개시제, 가소제와 함께 혼합하여 광고분자를 제조한다. 광반응성을 갖는 분자 크기의 무기물은 POSS(polyhedral oligomeric silsesquioxane)를 이용하는데 POSS는 뛰어난 분산도를 나타내므로 높은 투과도를 나타낼 수 있다. 또한 POSS의 광반응기들은 광민감도를 향상시켜 주고 높은 회절효율, 굴절율 차이 및 낮은 부피 수축율을 낮추어주는 효과도 나타낸다.본 발명에 의해서 제조되는 광반응성을 갖는 분자 크기의 무기물을 함유하는 광고분자는 우수한 투과도, 회절 효율 및 낮은 부피 수축을 가지므로, 홀로그램 정보 저장매체로의 응용이 가능하다

가교 광고분자를 이용한 부피 홀로그램의 기록 안정성에 관한 연구

학위논문(석사) - 한국과학기술원 : 생명화학공학과, 2005.2, [ ix, 74 p. ]The objective of the research is to synthesize a novel polymer matrix with outstanding dimensional stability and manufacture new photopolymer with excellent recording stability and optical quality for volume holographic application. In this study, a new photopolymer including polymer matrix with crosslinked structure based on epoxy and amine was prepared and investigated their optical performance. The polymer matrix was synthesized with various epoxy and amine groups under room temperature. With synthesized polymer matrix and photopolymer, thermal analysis and FT-IR experiment was carried to identify $T_g$ and conversion. The photopolymer was recorded by linear S-polarized DPSS green laser beams with 532nm wavelength and 6mW/㎠ beam intensity. The laser was split into two beams with an intensity ratio 1:1 by a beam splitter and recorded in θ = 15˚ from the normal of glass substrate. The intensities of the diffracted and transmitted light were measured with power meter by blocking one of the writing beams. A new photopolymer was investigated by comparing maximum diffraction efficiency, sensitivity, film thickness dependence, angular selectivity and grating image with PVA/AA linear system.한국과학기술원 : 생명화학공학과

Study on the relationship between polymer miscibility and optical properties of a photopolymer for 3D optical data storage device

Photopolymers are an attractive holographic material candidate for high-density data storage, optical filters, and display applications. Photopolymers gained great attention as a promising candidate materials for the holograms due to their relatively large refractive index modulation (Δn=10-2), high sensitivity, and low cost.However, most research works related to photopolymers are focusing on the holographic devices utilizing holographic materials, and thus the investigations on the materials itself for high-performance photopolymer, which guarantees the performance of holographic devices, cannot gained much attentions as much. In the present work, we investigated the relationship between polymer-polymer miscibility and optical properties of photopolymer in detail using thermal analysis, scanning electron microscope and optical property measurement

Epoxy Resin based Photopolymer Containing Double Bond terminated Pendant Group

Photopolymers have gained much interests as a representative recording medium for holographic data storage devices. Photopolymer consists of polymer matrix, photopolymerizable monomer, initiator, and photosensitizer. Exposure of photopolymers to non-uniform light initiates a photoreaction that occurs preferentially in regions of constructive interference. After exposure, photopolymer contains a record of the fringe pattern as a spatial variation of its chemical composition corresponding to the refractive index change. Photopolymer have promising merits such as high △n, high energetic sensitivity, and low cost in the application to holographic storage device. However, their application is limited by poor recording stability including temporal decay in performance and volume shrinkage during the recording process. To overcome the stability issues, we introduced a new photopolymer based on reactive polymer matrix containing pendant reactive group and optical properties by introduction of polymer matrix with pendant reactive group, which is expected that stability of recorded gratings can be enhanced. In this work, we successfully synthesized a very transparent matrix polymer whose thickness can be controlled quite easily. The maximum diffraction efficiency is not enough high until now, but the epoxy resin based photopolymer shows a due of enhancing the diffraction efficiency. Furthermore our new photopolymer showed a very interesting fluctuation of diffraction efficiency, which should be originated from overmodulation effect. It is a little different type of fluctuation from most of the reported overmodulation behavior in photopolymer. The origin of fluctuation in our photopolymer will be also discussed

A Novel photopolymer with reduced grating distortion

Photopolymers are an attractive holographic material candidate for high-density data storage, optical filters, and display applications. Photopolymers gained great attention as a promising candidate materials for the holograms due to their relatively large refractive index modulation (Δn=10-2), high sensitivity, and low cost. Recent research on a photopolymerizable holographic recording material is based on PVA/Acryl amide. Where as an existing PVA/AA photopolymer has merits of high refractive index modulation, good optical quality, high diffraction efficiency and moderate sensitivity, but volume shrinkage during photopolymerization is a serious problem. In this study, we synthesized a novel photopolymer to prevent volume shrinkage by introduction of the chemically crosslinked polymeric binder containing pendant double bond which will react with the photopolymerizable monomer during recording process. Since three dimensional(3D) network binder binds recorded grating, our photopolymer is expected to have an advantage of preventing grating distortion due to the low volume shrinkage

Gel Type Proton Conducting Polymer Electrolyte forPolymer Electrolyte Fuel Cell at high temperature,Polymer Electrolyte Fuel Cell comprising theElectrolyte, and Preparation method thereof

본 발명은 고분자 전해질 연료전지의 수소 이온 전도성 고분자 전해질 및 고분자 전해질형 연료전지와 그 제조방법에 관한 것으로, 보다 상세하게는 말단기가 술폰화된 덴드라이머를 전해질로 하여 100℃ 이상에서 뿐만 아니라 0℃ 이하의 저온에서도 우수한 전도도를 가지는 젤형 수소 이온 전도성 고분자 전해질, 이를 포함하는 고분자 전해질형 연료전지 및 그 제조방법을 제공한다