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The effects of heat stabilizer systems on the thermal stability and processability of self‐made vinylidene chloride‐methyl acrylate copolymer (PVDC‐MA) film were investigated via accelerated aging test, Congo red test, FTIR, DMA, and TG‐FTIR. These results displayed that CaSt2/ESO performed excellently in synergistic inhibition of PVDC‐MA thermal degradation. Especially, when the mass ratio of CaSt2/ESO was 1.5:1.5, the static thermal stability time of PVDC‐MA was increased from 14.5 to 46.5 min. The kinetic calculation results also verified this point. Compared with pure PVDC‐MA, the average apparent activation energy (Ēa) of thermal degradation reaction of PVDC‐MA stabilized by CaSt2/ESO enhanced from 144.1 to 169.7 kJ mol−1 (α0 ≤ 0.1), indicating that the thermal stability of PVDC‐MA in the initial thermal degradation stage was dramatically improved by CaSt2/ESO. Moreover, the mechanism of the effect of CaSt2/ESO on PVDC‐MA in the initial thermal degradation stage was further explored by the generalized master plot methods. The kinetic analysis result suggested that under the synergistic effect of CaSt2/ESO, the mechanism model followed by the degradation of PVDC‐MA changed essentially (the three‐dimensional diffusion thermal degradation mechanism transformed into two‐dimensional diffusion).

Flexible organic light emitting diodes (FOLEDSs) require a barrier layer with transparency, thermal stability, and flame retardance to prevent water from inducing the corrosion of electrode and ultimately deterioration. Herein, HPS spheres were incorporated into the vinylidene chloride-methyl acrylate (VDC-MA) matrix to enhance the water vapor barrier property, thermostability, and anti-glare effect. Scanning electron microscopy showed that HPS spheres were more compatible with VM (89.86-10.14) by presenting better water vapor barrier property rather than with VM (92.38-7.62). The anti-glare effect of composite film was improved with HPS spheres, while the transparency still maintained over 80%. Thermogravimetric analysis showed that the weight loss still maintained over 50% with the incorporation of HPS spheres, indicating significant improvement compared with control VDC-MA films. Our research supplies an effective approach to prepare transparent and flame retardant hybrid films with enhanced water vapor barrier, thermostability, and anti-glare properties, which is promising in the encapsulation of FOLEDSs and other electronics areas. K E Y W O R D S anti-glare, barrier, flame retardant, polysilsesquioxane spheres, vinylidene chloride copolymer 1 | INTRODUCTION Flexible polymer films have increasingly replaced glass and metals as flexible electronic grows. Flexible organic light emitting diodes (FOLEDSs) require a barrier layer to prevent water and gases from inducing the corrosion of electrode and ultimately deterioration in the lifetime of device. 1 To guarantee the performance of FOLEDs, the transparency, thermal stability, and flame retardance of barrier materials should be considered. 2,3 Vinylidene chloride (VDC) copolymers with symmetrical chemical structure and high crystal degree possess excellent barrier properties, chemical resistance, flame retardance, and so forth. 4,5 However, the thermal stability of VDC copolymers are restricted when applied in the encapsulation of FOLEDs and other electronics. Recently, many research studies have focused on using SiO 2 particles 6,7 or clay platelets 8,9 to enhance the thermostability and oxygen barrier property of VDC Dongqiao Zhang and Jiemin Yi contributed equally to this study.