Photocrosslinked polymer and interpenetrating polymer network for nonlinear optics

Abstract

ABSTRACT:Two photocrosslinkable NLO polymers of poly(glycidyl methacrylate) substituted with 4-nitro-4Ј-hydroxyl stilbene (PGMAS) and acryloyl-functionalized epoxybased polymer (PENAA) carrying 4-nitroaniline moieties were synthesized and characterized. By using the sulfonium salt cationic photoinitiator BDS ⅐ 2PF 6 which can induce cationic or/and radical polymerization, the photocrosslinking of PGMAS and the interpenetrating polymer network (IPN) formed by the photocrosslinking of PGMAS and PENAA simultaneously were reported. The poled and photocrosslinked polymer films and IPN films exhibit relatively stable second-order nonlinear optical activity. The influence of stilbene isomerization in PGMAS films with different crosslink densities on the SHG stability was also investigated.

Covalent attachment of chromophores to chlorinated copolymers for optical waveguides: Synthesis and optical characterization

“…8) show that both polymers have good thermal stability, temperatures of initial decomposition being 353 and 363 C for poly(CS-GMA) and poly (CS-GMA-MA19), respectively ( Table 2). The observed values are in a good agreement with literature data related to poly(CS) [56], while poly(GMA) is known to start degrading at lower temperatures [31,34]. This result, alongside the observation that the degradation process occurs in a single weight-loss step, suggests that chlorostyrene moieties enhance the thermal stability of glycidyl methacrylate segments.…”

“…However, drawbacks in this method are related to the evolution of hydrogen chloride in the course of reaction causing a potential decrease in the efficiency of dipole polarization of the resulting material [23]. One way to overcome this problem is to replace chloride with other acrylates bearing reactive groups, such as epoxy ring in GMA [33,34]. An additional advantage of using GMA as a co-monomer is the possibility of facile chemical crosslinking of the resulting polymer through epoxy groups by means of photo-induced polymerization at relatively low temperatures, without excluding oxygen from air [35][36][37][38].…”

Poling and crosslinking processes in NLO polymers

“…However, the ideal approach would allow for separation of poling and crosslinking reactions through the use of an orthogonal initiation process. Photocrosslinking represents one clear alternative, but comparatively few examples exist in the literature . This is in part due to the difficulties inherent to photoinitiation in the presence of strongly absorbing chromophores.…”

“…Photocrosslinking represents one clear alternative, but comparatively few examples exist in the literature. 24,[32][33][34] This is in part due to the difficulties inherent to photoinitiation in the presence of strongly absorbing chromophores. Our early efforts resulted in minimal improvement of thermal stability, which was attributed to poor crosslinking conversion.…”

Photopolymers: Synthesis and Characterization of Poly(3-methacryloyloxystyryl-2-naphthyl ketone)

“…[1,2] Polymers with pendant photosensitive groups have been used as photoresists. [3,4] These photosensitive polymers can be applied in the fields of microlithography, [5,6] printing materials, [7] nonlinear optical materials, [8] liquid crystals, [9] etc.…”