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Events. Structure. Revenue. Portfolio. Capabiliy. Philosophy. Support. Competence. Nanoparticles as UV absorbers. Nano Functional Materials. (NFM) project. יום עיון : יישומי ננו טכנולוגיה בתעשיית הפלסטיקה והגומי . שנקר, בי"ס גבוה להנדסה ועיצוב . ינואר 2007. Support program for:
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Events Structure Revenue Portfolio Capabiliy Philosophy Support Competence Nanoparticles as UV absorbers. Nano Functional Materials. (NFM) project. יום עיון: יישומי ננו טכנולוגיה בתעשיית הפלסטיקה והגומי . שנקר, בי"ס גבוה להנדסה ועיצוב. ינואר 2007.
Support program for: Generic Technological R&D Transfer of technology: Academia to industry. Operational framework is a consortium of industries and research institutes. 66% government grant. MAGNETמחקר גנרי טכנולוגי
Consortium frame work: 12 Industries. Researchers from 3 academic institutions. Three leading projects: Manufacturing and stabilization of nano particles in liquid phase. Compounding nano particles into polymers matrix. De-agglomeration of nano particles. MAGNET/2
Functional properties with almost no outward migration from the polymer. Transparent. Positive interaction with polymer to obtain specific advantages. e.g. nanoclays –improves mechanical properties and transparent. Why nanoparticles additives ?
Challenges: Agglomeration interferes with functional dispersion. Surface treatments, dispersing agents… Adjusting process parameters. Evaluation of the dispersion quality: TEM, SEM and… Areas of activity: UV absorbers/blockers: nanosized ZnO, organic UVA nano-particles. Flame retardants. Kafrit’s activities:
Without UV blocking With UV blocking UV absorbed/blocked films for pest control. Advantages of UV absorbers in Greenhouse Films: • Distorts harmful insects activity. • Controls viral plant diseases vectored by insects*. In addition: • Protects the polymer from photo oxidative degradation. • Prevents petal blackening. *This is the reason why, in commercial applications, UV blocked AgriFilms is also called “AntiVirus”
Advantages of UV absorbers in Packaging Films: Benefits:UV light filtering can prevent undesirable changes of the color, odor, flavor and nutrients. Effective blocking in thin films – no migration/”blooming”. no UV Myoglobin (red) Metmayoglobin (brown) UV UV blocking/Packaging. UV, O2
Deterioration of UV blockage effect. UV absorbers are lost as the results of photodecomposition and migration.
UV blocking – ZnO. Preliminary particles size 50-60 nm. In practice: aggregates of 1-2 mm.
ZnO. Homogenous dispersions of Influence of dispersing aid/surfactant type on ZnO dispersion. • Compounding with dispersing aids of different functionality. • Haze (forward light scattering) as the dispersion’s quality parameter.
Dispersion aids and ZnO. With… Without… By Prof. Y. Cohen (Technion)
Long lasting UV blocking effect. ZnO - UV blocking effect maintains for longer period of time compares to the organic UVA.
Org UVA_1 ZnO based_1 ZnO based_2 Org UVA_2 Long lasting UV blockage/Pesticides influence. Faster deterioration of UV blockage in the formulations based on nanosized ZnO compares to the organic UVA as the result of sulfur burning. There is strong relation between UV blockage deterioration and amount of sulfur applied.
ZnO nano - effect on organic UVA migration. Without ZnO. With ZnO. • Nanosized ZnO slows down migration rate of organic UVA. • Potential application for thin packaging films.
Dispersion is feasible. Chemistry: Improved dispersion with the proper surfactant. High transparency and low light scattering. Further steps: influence of processing conditions on the nonoparticles dispersion. Long lasting UV blockage: Long term effect without agrochemicals. Further steps: influence of particles surface treatment onagrochemical’s resistance. Migration control by nanoparticles. Intermediate conclusions.
Emulsion polymerization of UVA monomers (acrylate substituted BZT). Novel UVA organic particles:Synthesis of UV absorbing nano particles (1)Prof. S. Margel
BZT BZT Emulsion polymerization.
TEM picture of polymerized BZT. Average particles size 280 20 nm.
Synthesis of UV absorbing nano particles(2) • But- synthesis products aggregate. • Dispersion is possible: • surfactants compatible with polyolefins. • drying on the porous resin.
X 1000 Polymerized BZT / PE film. Dispersion of polymerized BZT particles in LDPE.
BZT_0.75% Polymerized BZT/ UV absorption efficiency. Higher concentration of polymerized nanoparticles is needed to achieve UV blockage. “Waste” of UVA moieties due to polymerization.
Reduction of the particles size. Grafting of BZT brushes on the surface modified silica nano particles: Further steps:
Nano SiO2 particles. Nano sized SiO2 . Surface Modified SiO2
Novel nanosized UVA particles were synthesized. Homogeneous dispersion in PO matrix. (adjustment of proper surfactants and drying conditions of synthesis products). Not sufficient efficiency of UV blockage. Further steps:improvement UV absorption efficiency by Reduction of particle size. Grafting of UVA monomer on nanosized silica. Organic UVA particles/Summary.
UV blocking–particles and organic compounds. Normalized blocking efficiency
Dispersion without agglomeration Use dispersion aids. Evaluation of the dispersion quality: TEM, SEM and… Understanding the effects of the extrusion parameters on the dispersion quality. Personnel and environmental safety. The challenge of nano particles compounding
High loading – no AF Low loading - AF Effect of ZnO loading on AF