Synthesis of photoaddressable polymeric networks having azobenzene moieties and alkyl-chains-containing compounds
We discuss the synthesis of new optically active polymeric networks containing azobenzene moieties and different alkyl-chaincontaining compounds. An epoxy resin based on diglycidyl ether of bisphenol A (DGEBA) was reacted with metaxylylenediamine (MXDA). An azo prepolymer (TAZ) was synthesized by re...
| Authors: | ; ; |
|---|---|
| Format: | Article |
| Status: | Published version |
| Publication date: | 2013 |
| Country: | Argentina |
| Institution: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repository: | CONICET Digital (CONICET) |
| Language: | English |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/2571 |
| Online Access: | http://hdl.handle.net/11336/2571 |
| Access Level: | Open access |
| Keyword: | AZOPOLYMER EPOXY NETWORKS PALMITIC ACID PHOTOINDUCED ANISOTROPY https://purl.org/becyt/ford/2.5 https://purl.org/becyt/ford/2 https://purl.org/becyt/ford/2.4 https://purl.org/becyt/ford/1.4 https://purl.org/becyt/ford/1 |
| Summary: | We discuss the synthesis of new optically active polymeric networks containing azobenzene moieties and different alkyl-chaincontaining compounds. An epoxy resin based on diglycidyl ether of bisphenol A (DGEBA) was reacted with metaxylylenediamine (MXDA). An azo prepolymer (TAZ) was synthesized by reaction between Disperse Orange-3 and DGEBA. Reaction between palmitic acid (PA) and DGEBA was performed using triphenylphosphine as catalyst of the epoxy–acid reaction employing variable molar ratios of epoxy to carboxyl groups (r = 1, 2, 4). These precursors were called PA1, PA2 and PA4. Crosslinked epoxy-based azopolymers containing variable PA-based precursor content and constant chromophore concentration equal to 20 wt% TAZ were synthesized. Their reversible optical storage properties were studied and compared. It was found that the optical response is a direct consequence of the morphologies generated, and that crystallization of PA-based precursor can take place. When the PA-based precursor is not covalently bonded to the matrix, e.g. PA1, the remaining birefringence is high. PA4-modified materials present a completely different response, showing a behaviour that could be of great importance in the development of optical switchers. In this case, the organic tails remain dissolved in the matrix and unable to crystallize, giving a typical ‘on–off’ response. |
|---|