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It is shown in this paper that a polymer, MA-PEG 1000-DGEBA (MP1D), exhibits antireflection, substrate-dependent photoluminescence (SDP), wide band-gap, and photoconduction characterization. MP1D was synthesized from maleic anhydride, polyethylene glycol 1000, and bisphenol-A diglycidyl ether. Self-assembled nanoparticles embedded in MP1D film and ranging from 2.5 to 31.6 nm are observed, which could be expected as scatterers to enhance light trapping and extraction. The size of the nanoparticle increases with the concentration of the MP1D solution. Besides solution concentration, the nanoparticle dimension could be modified by the chain length of polyethylene glycol in the polymer synthesis. The effects of solution concentration, annealing temperature, annealing period, and substrate on the photoluminescence (PL) of MP1D films are examined. Increasing solution concentration increases PL intensity. However, aggregation-caused quenching is explicit as the solution concentration exceeds 100 mM. PL intensity increases with annealing temperature, which could be attributed to crystallinity improvement. PL intensity increases with increasing the annealing period from 0.5 to 2 h. Nonetheless, as the annealing period exceeds 2 h, PL quenching is emerging, which could be due to aggregation. It is expected that MP1D could be a promising candidate for host materials and MP1D film could play a multifunctional role (antireflective and light-trapping functions) in optoelectronics.

Nonconjugated polymers have been synthesized from maleic anhydride, poly(ethylene glycol), and bisphenol-diglycidyl ether without utilizing any solvent. The polymeric thin films produced by the nonconjugated polymers were spin-coated on ITO coated glass and Si substrates. Self-assembly nanoparticles (1.6-6.2 nm) are observed. It is proposed that the nanoparticle is constructed through a self-assembly process with bisphenol-A aggregates and poly(ethylene glycol) moieties. The photoluminescence spectrum of the polymeric thin film on ITO peaks at near 450 nm that spans from 360 to 610 nm under 266 nm excitation. The polymeric thin film exhibits the excitation-wavelength-dependent photoluminescence that the emission peak shifts toward longer wavelength (about 11 nm) when the excitation wavelength increases from 266 to 325 nm, which is attributed to nanoparticle size distribution. Meanwhile, the substrate-dependent photoluminescence has been also observed that the PL peak of the polymeric thin film spin-coated on Si shows a blue shift (about 9 nm) compared with that on ITO, which probably arises from the dielectric screening. The highest occupied molecular orbital energy of the polymeric thin film is about -9.4 eV. The optical band gap is about 3.28 eV. The nonconjugated polymer is expected to use as a host material in optoelectronic applications.

anhydride-poly(ethylene glycol) co-polymer (A-PEGCP) has been synthesized from maleic anhydride, poly(ethylene glycol) and bisphenol-A diglycidyl ether without using any organic solvent. The thin films produced from A-PEGCP solution were spin-coated on ITO-coated glass. The nanoparticles are observed in the thin films. It is proposed that the nanoparticle is built by a self-assembly process with bisphenol-A aggregates and poly (ethylene glycol) moieties. The effects of concentration, thermal annealing, excitation wavelength and moisture on the optical and nanostructured characterization of the thin films are investigated in this study. Photoluminescence (PL) spectrum of the thin film on ITO-coated glass has a peak of about 450 nm that extends from 360 to 550 nm under 325 nm excitation. The increase in PL intensity is accompanied by a red shift of PL spectrum as concentration increases. Moreover, the slightly red shift of PL spectrum is also observed as annealing temperature increases. Meanwhile, PL intensity negligibly decreases with annealing temperature. The degradation in PL intensity is apparent due to moisture. The excitation-wavelength dependent photoluminescence (EWDP) is observed in the thin film. UV-Vis absorption spectra of the thin films are red-shifted with concentration due to more molecular aggregation. The highest occupied molecular orbital (HOMO) energy is −9.52 eV. The optical band-gap energy is 4.09–4.44 eV.