Organic-inorganic hard coating layer formation on plastic substrate by UV curing process

Abstract

Efficient methods for making organic-inorganic hard coating layers on a polymethylmethacrylate substrate were developed and optimized to improve the mechanical and optical properties. Colloidal silica was coupled with methacryloxypropyltrimethoxysilane to make Si-O-Si bonds before incorporating them into the organic phase of the monomer and oligomer. A combination of photoinitiators with different absorption bands could utilize the UV light throughout the entire wavelength range to show better curing results than the case of a single photoinitiator with a limited absorption band. The effects of the photoinitiator in terms of the mixing ratio and concentration in the coating solution were examined and optimized. The UV curing reactivity was improved using a mixture of different initiators with different absorption bands, and 4:1 ratio mixture of Irgacure 184 and Irgacure 907 showed the best hard coating properties, such as hardness and impact strength. The optimum initiator content was determined to be 5 wt% in the hard coating solution. However, too much initiator resulted in excessive primary radical reactions of the monomers, and the competition of primary radicals reduced the conversion and initiator efficiency.

Laminated film composites of multilayered plastic film and inorganic polymer binder as an alternative to transparent and hard glass

“…Various attempts have been made to improve the modulus of bulk plastic materials and surface softness by using organic-inorganic hybrid composites and coating techniques. 13 Recently, polyhedral oligomeric silsesquioxane (POSS) nanocages have attracted attention owing to their observed mechanical and physical enhancement of a variety of organic systems as an inorganic polymer reinforcement (Figure 1c). 14,15 In particular, the incorporation of a reactive group containing POSS facilitates consolidation through simple ultraviolet (UV) or thermal exposure in the presence of suitable additives.…”

Preparation of polymer/silica hybrid hard coatings with enhanced hydrophobicity on plastic substrates

“…Hard coatings of organic-inorganic hybrids emerge and quickly become the target of extensive research since 1990s [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. It is found that in most cases the incorporation of inorganic nanoparticles improves the mechanical and thermal properties of plain organic coating considerably.…”

“…For example, in previous works, silica nanoparticles containing methacrylate groups have been prepared by reacting with a silane, 3-(trimethoxysilyl)propyl methacrylate (MSMA), in a sol-gel process [8,[19][20][21][22][23][24][25]. The modified silica nanoparticles would undergo co-polymerization with the binder to form a strong organic-inorganic hybrid via a UV-curing process.…”

Syntheses and characterization of functionalized polynorbornene dicarboximides for flexible substrates

“…Such polymer substrates are usually fabricated by depositing transparent conducting oxide (TCO) film such as tin‐doped In 2 O 3 (ITO) film on a certain transparent polymer film instead of a glass. Common plastic materials as substrates include polyethylene terephthalate (PET), polycarbonate, polypropylene adipate, and polymethyl methacrylate (PMMA), etc. However, these plastic substrates can be severely damaged at high temperature (200°C–300°C for sputtering method) during deposition process, due to their intrinsic low thermal and mechanical properties compared to other inorganic or metal substrates.…”