Comprehending Grafted Silane

A modified version of silane chemical called grafted silane has become an important ingredient in adhesive film development for photovoltaic (PV) applications. The covalent bonding of silane molecules to the polymer chains seen in sticky films is referred to as “grafted silane.” The polymer’s functional groups and the silane coupling agent react chemically to produce this attachment. By acting as spacers between the polymer chains, the grafted silane molecules improve adhesion and substrate compatibility.

Synthesis of Silane Grafts

Grafted silane is synthesized using a multi-step process. First, the adhesive characteristics and compatibility of the polymer matrix with the required substrate are taken into consideration while selecting it. PV films typically consist of polyolefins and ethylene-vinyl acetate (EVA).

Next, the specific functional groups and reactivity of the silane coupling agent are taken into consideration. Typically, the coupling agent consists of a functional group (like methacrylate, epoxy, or amino) that can react with the polymer matrix and a silane group (Si-O-Si).

By adding the coupling agent to the polymer matrix via a variety of techniques, including solution mixing, melt blending, or reactive extrusion, the grafted silane is created. The silane molecules form covalent bonds with the polymer chains as a result of the coupling agent’s functional groups reacting with the polymer matrix.

Grafted Silane’s Function in PV Adhesive Films

The use of grafted silane is essential for improving PV films’ overall performance and adhesive qualities. The interfacial adhesion between the adhesive film and other substrates, including glass, backsheet, or encapsulant materials, is improved by the addition of grafted silane.
As coupling agents, the grafted silane molecules create a solid chemical link between the substrate and the polymer matrix. This increased adherence contributes to the PV module’s improved mechanical stability, decreased moisture infiltration, and prevention of delamination.

Additionally, grafted silane enhances the compatibility of the PV module’s various parts, including the backsheet and encapsulant. Longer operational lives, increased resistance to environmental stressors, and greater module durability are the results of this compatibility upgrade.

Grafted silane can also alter the adhesive film’s surface characteristics, such as surface energy and wetting behavior. This adjustment makes it possible for the adhesive film to distribute more evenly across the substrate, improving coverage and minimizing the creation of voids. Better electrical contact between the PV cells and the encapsulant is another benefit of the improved wetting behavior, which raises the performance of the module.

L'adhérence entre les films d'emballage photovoltaïques et les panneaux solaires en cristal de silicium a un impact important sur le rendement des panneaux photovoltaïques. L'étape clé pour obtenir cette adhésion est l'ajout d'additifs pour les films d'emballage photovoltaïques. Après l'ajout d'additifs, l'adhérence entre le film et le panneau solaire en cristal de silicium sera effectivement améliorée, ce qui permettra d'accroître le rendement.

Grafted silane presents a substantial opportunity to improve PV adhesive films’ performance and adhesive qualities. Grafted silane enhances the adhesion, compatibility, and endurance of the films by covalently attaching to the polymer matrix. Better interfacial adhesion, less delamination, better wetting behavior, and higher module performance are all made possible by the application of grafted silane.The silane photovoltaic additives have greatly improved the aging problem of traditional coupling agents, improved the reliability and efficiency of photovoltaic modules, and enabled photovoltaic modules to have a revolutionary development!

COACE is committed to the R&D, production and service of additifs pour films d'emballage photovoltaïques, and has a R&D team led by several senior engineers and Ph.D.s. COACE’s silane photovoltaic packaging film additives have the characteristics of high transparency and low crystal point. , with high grafting rate, good fluidity and high resistivity, it is favored by the majority of users!