| It has been of vital significance to afford enhanced performance and added functionalities to polymers.Toward this end,laser holographic processing on photopolymer-based composites is believed to be an efficient approach,which enables the generation of polymer composites with ordered structure.During the laser holographic processing,it remains challenging to tailor the micro-structures of polymer composites for the purpose of achieving enhanced performance.Thus,it is required to get deeper insights into the diffusion and phase separation behaviors of hybrid systems during the laser holographic processing,for the aims of developing ordered polymer composites with higher performance and more functions.In this dissertation,different photopolymer-based hybrid systems were formulated using a photoinitibitor,varied monomers and photo-inert components.Three different polymer composites with ordered structures were formed subsequently by employing the laser holographic processing.They are the photopolymer/ZnS nanoparticles composites,photopolymer/liquid crystals/ZnS nanoparticles composites and photopolymer/ionic liquid composites,respectively.The polymer composites were investigated sequentially considering that the diffusion/phase separation behaviors vary from simple to complicated and material functions change from sole to diverse.The dependence of micro-structures on the diffusion/phase separation behaviors during laser holographic processing was illustrated in detail.The structure-property relation of polymer composites was also depicted.Firstly,we investigated the photopolymer/ZnS nanoparticles hybrid system.We synthesized mercaptoethanol capped ZnS nanoparticles with a diameter of?5 nm through a one-pot method,and then formulated holographic mixtures with the synthesized ZnS nanoparticles,hybrid monomers and the photoinitibitor.We successfully obtained polymer/ZnS nanocomposites with ordered structure through laser holographic processing.The influences of the composition of photoinitibitor,ZnS nanoparticles content and light intensity on the properties of the obtained polymer/ZnS nanocomposites were disclosed.We achieved high performance photopolymer/ZnS nanocomposites with ordered structure and as high as 93.6%of diffraction efficiency,0.0266 of refractive index modulation.In addition,for an aim of roughly describing the formation process of polymer/inorganic nanocomposites with ordered structure,we established a novel exponential correlation between the inorganic nanoparticles segregation degree and the ratio of gelation time to holographic mixture viscosity.We also reconstructed and displayed 3D images that were clearly identifiable to the naked-eye through a master holography technique,opening a versatile class of potential applications in stereo-advertisements and anticounterfeiting.Secondly,we investigated photopolymer/liquid crystals/ZnS nanoparticles hybrid system.The dissolution of photoinitibitor in hybrid monomers was improved significantly by using N,N-dimethylacrylamide.The influences of N,N-dimethylacrylamide on the micromorphology and performance of polymer/liquid crystals composites with ordered structure were deeply studied.Polymer/liquid crystals composites with 98.2%of diffraction efficiency and well-defined scaffolding structures were fabricated.The threshold voltage of the polymer/liquid crystals composites with ordered structure was decreased from 11.6 to 2.5 V/?m by incorporating 8 wt%of ZnS nanoparticles while maintaining the advantages of high diffraction efficiency and well-defined scaffolding structures.Furthermore,we demonstrated the diffusion process of photopolymer/liquid crystals/ZnS nanoparticles hybrid system during laser holographic processing.The mercaptoethanol capped ZnS nanoparticles were confirmed to be distributed in polymer rich regions once the holography was implemented.Finally,we investigated photopolymer/ionic liquid hybrid system.Polymer/ionic liquid composites with ordered structure were fabricated through laser holographic processing.These polymer composites are not only able to be used as high performance holographic gratings but also polyelectrolytes with anisotropic conductivity.The effect of monomer structures on the micromorphology of polymer/ionic liquid composites with ordered structure was illustrated.The relationship between the micromorphology and performance of polymer/ionic liquid composites with ordered structure was discussed.When using 2-ethylhexyl acrylate,N-vinyl pyrrolidone and hyperbranched acrylate as hybrid monomers,the micromorphology of the obtained polymer/ionic liquid composites with ordered structure were well-defined with scaffolding morphology,and the conductivity anisotropy ratio could be achieved as 2.7.When employing 2-ethylhexyl acrylate,N-vinyl pyrrolidone,ethylene glycol dimethacrylate and pentaerythritol tetraacrylate as hybrid monomers,porous structures were given in the obtained polymer/ionic liquid composites.The conductivity anisotropy ratio of polymer/ionic liquids composites with ordered and porous structures was lower,however,high diffraction efficiency and refractive index modulation could be achieved as 95.2%and 0.0190,respectively. |
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