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A series of 0-3 composites of lead zirconate titanate (PZT) and nylon77 was prepared with PZT volume fractions between 0.1 and 0.6 using the combined method of solvent casting and hot pressing. Depending upon the volume fraction of PZT, the relative permittivities of the composites were found to be in the range of 200-2000 when measured at the highest practically possible temperature of 200 C. As PZT volume fraction increases, both the relative permittivity and the piezoelectric constant d 33 increase. The best combination of electrical properties and flexibility was obtained in 0.5 PZT volume fraction composites. At this composition, the remanent polarization P r of composites was up to 1000 mC/ m 2 at the applied electric field of 40 MV/m and it increased with an increase in temperature. The highest piezoelectric strain coefficient d 33 was obtained at 17 pC/ N in 0.6 PZT volume fraction composites.

Single-purpose greenhouse films such as UV-blocking, NIR-blocking, or ultrathermic films are commonly developed in various climate regions. However, multifunctional films of combined functions are rarely explored, especially in the tropical regions. In this research, a multifunctional film having high UV filtration, high NIR reflection, and good light diffusion was developed for a greenhouse cover application in tropical regions. Effects of type, quantity, and particle size of additives on optical properties (280–2500 nm) and mechanical properties of 3-layer laminated films comprising 90% LLDPE/10% EVA polymer matrix and additives were studied. Results show that properties of those films are adjustable by varying types, particle size, and content of additives. The UV transmission of the film was ranged from 13.7 to 32.7 %T, NIR reflection from 12.1 to 19.8 %R, and %haze diffusion from 39.5 to 72.3 where photosynthetically active radiation (PAR) transmission was in the range of 62.6–78.9 %T. Those films exhibit tensile strength of 18–24 MPa, modulus of elasticity of 200–280 MPa, and elongation at break of 610–810%. A field test of the newly developed films as a cover for a greenhouse of 6 m wide ×24 m long ×4.3 m high with double roof design showed a better quality of plant growth in terms of weight, height, and bush width compared to a 7% UV absorber commercial film.

Hollow polymeric nanoparticles have attracted vast attention as UV-shielding materials in personal care products due to their excellent light scattering characteristics and low density. In this work, a process for fabricating biocompatible/degradable poly­(lactic acid-co-glycidyl methacrylate), P­(LA-co-GMA), hollow nanoparticles via one-step phase inversion emulsification is examined, to gain insights into their formation mechanisms and optimization of the process parameters. The migration of poly­(vinyl alcohol) (PVA) (stabilizing agent) from the oil droplet to the oil/water interface while entangled with cross-linked P­(LA-co-GMA) chains and the fast evaporation rate of the chloroform solvent play an essential role in the hollow structure formation. Under optimum conditions, monodispersed hollow nanoparticles, with an average size of 500–700 nm and good colloidal stability, are obtained. The as-prepared hollow nanoparticles exhibit high UV shielding capabilities and low toxicity. The nanoparticles show high stability under UV exposure but can be completely degraded within 24 weeks under accelerated hydrolysis conditions. The materials have a high potential for use as environmental-friendly UV-shielding additives in cosmetic applications.

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A series of 0–3 composites of lead zirconate titanate (PZT)/ferroelectric odd–odd nylons was prepared with variations in the size of PZT powder and in the dipole density of ferroelectric odd–odd nylons. The as‐formed PZT powder prepared by a spray‐drying technique consists of spherical granules composed of large numbers of interconnected fine particles. Electrical properties of the composites as a function of the size of this particular PZT powder and the dipole density of ferroelectric odd–odd nylons were studied. With the PZT powder sintered at 1100°C, the relative permittivity, polarization, and piezoelectric strain coefficient (d33) of the PZT/nylon composites increased with increasing powder size of PZT. The electrical properties of the composites also increased as the dipole density of the polymer increased. The PZT/nylon 57 composite exhibited a high‐relative permittivity and piezoelectric strain coefficient d33 due to an increase in its dipole density. The optimum relative permittivity and polarization of this composite were obtained by the PZT with an average granule size of 95 μm. The highest piezoelectric strain coefficient d33 of the 0–3 composite was found at 28 pC/N whereas the relative permittivity was approximately 73.