摘要 |
The invention relates to high Tg monolithic and multi-layer thermoformable film or sheet useful as a backsheet on a photovoltaic module (PV). A methacrylic-based material is preferred. The film or sheet is formed of a composition having a Tg greater than 110° C. The methacrylic composition may be a blend of a polymethyl methacrylate polymer and a miscible or semi-miscible high Tg polymer, or may be a copolymer containing primarily methyl methacrylate monomer units. The backsheet is optionally covered with a fluoropolymer or acrylic/fiuoropolymer covering on the outside (side facing the environment). The back-sheet can be clear, white, and/or pigmented. The film or sheet is especially useful in concentrating photovoltaic modules (CPV), and is also useful in thin film photovoltaic modules. |