Use of a fluid polymeric composition for encapsulating photovoltaic modules

1. A polymeric composition configured for use as an encapsulant in a photovoltaic module, said polymeric composition comprising a copolymer which comprises an ethylene monomer and a carboxylic acid vinyl ester comonomer, the carboxylic acid vinyl ester comonomer representing between 5% and 50% by weight, relative to the total weight of the copolymer, and the polymeric composition having a Brookfield viscosity, measured at 120° C., of between 10,000 mPa·s and 25,000 mPa·s,

wherein the copolymer represents between 92% and 99.9%, relative to the total weight of the polymeric composition.

2. The polymeric composition of claim 1 , wherein the carboxylic acid vinyl ester comonomer is chosen from the group consisting of vinyl acetate, vinyl 2-ethylhexanoate, vinyl octanoate and versatic acid vinyl ester.

3. The polymeric composition of claim 1 , wherein the copolymer comprises from 10% to 40% by weight of carboxylic acid vinyl ester comonomer, relative to the total weight of the copolymer.

4. The polymeric composition of claim 1 , wherein the copolymer consists of an ethylene monomer and of a carboxylic acid vinyl ester comonomer.

5. The polymeric composition of claim 1 , wherein the polymeric composition further comprises a crosslinking agent, the crosslinking agent representing in total between 0.1% and 5%, relative to the total weight of the polymeric composition.

6. The polymeric composition of claim 1 , wherein the polymeric composition has a Brookfield viscosity, measured at 120° C., of between 12,000 mPa·s and 23,000 mPa·s.

7. A process for encapsulating a photovoltaic module, comprising:

a) obtaining a polymeric composition according to claim 1 , and a crosslinking agent;

b) forming a stack comprising, in order, a protective backsheet, a first layer of the polymeric composition, an assembly of photovoltaic cells, a second layer of the polymeric composition, and a protective front sheet; then

c) applying an activation treatment suitable for the crosslinking agent in order to crosslink the composition.

8. The process as claimed in claim 7 , wherein the crosslinking agent is a thermally activated crosslinking agent and step c) consists of heat treating the stack at a temperature above the activation temperature of the agent for crosslinking the polymeric composition.

9. The process as claimed in claim 7 , wherein the process is carried out continuously.

10. The polymeric composition of claim 1 , wherein the carboxylic acid vinyl ester comonomer is vinyl acetate.

11. The polymeric composition of claim 1 , wherein the copolymer comprises from 15% to 35% by weight of carboxylic acid vinyl ester comonomer, relative to the total weight of the copolymer.

12. The polymeric composition of claim 1 , wherein the copolymer represents between 97.5% and 99.5%, relative to the total weight of the polymeric composition.

13. The polymeric composition of claim 1 , wherein the polymeric composition further comprises a crosslinking agent, the crosslinking agent representing in total between 0.5% and 2.5%, relative to the total weight of the polymeric composition.

14. The polymeric composition of claim 1 , wherein the polymeric composition further comprises a crosslinking agent, the crosslinking agent representing in total between 0.7% and 2% by weight, relative to the total weight of the polymeric composition.

15. The polymeric composition of claim 1 , wherein the polymeric composition further comprises a coupling agent.

16. The polymeric composition of claim 15 , wherein the coupling agent is an organic titanate or an organic silane.