Resin composition comprising a specific crosslinking agent
A resin composition is based on a resin selected from the group consisting of vinyl ester resins and unsaturated polyester resins, a crosslinking initiator and a crosslinking agent of general formula (I) in which i is an integer between 2 and 4, X is an i-valent group comprising at least one ring of 6 atoms selected from carbon and nitrogen and comprising at least 2 heteroatoms selected from nitrogen and oxygen, and R is an acrylate group, methacrylate group, vinyl group, alkenyl group bearing an unsaturated carbon at the chain end, or alkynyl group bearing an unsaturated carbon at the chain end.
1. A pneumatic tire comprising: a crown reinforced by a crown reinforcement; two sidewalls; two beads, each bead being reinforced with a bead wire; and a carcass reinforcement wound around the bead wire in each bead;
wherein the carcass reinforcement, the crown reinforcement, or both comprise a composite; wherein the composite comprises at least one fiber and a resin composition in a crosslinked state; and wherein the resin composition is based on:
a crosslinkable resin selected from the group consisting of vinyl ester resins and unsaturated polyester resins;
a crosslinking initiator, present in an amount of from 0.5% to 3% by weight of the resin composition; and
a crosslinking agent of general formula (I), present in an amount of from 2% and 15% by weight of the resin composition,
in which:
i is an integer of 2 to 4,
X is an i-valent group comprising at least one ring of 6 atoms selected from carbon and nitrogen and comprising at least 2 heteroatoms selected from nitrogen and oxygen, and
R is an acrylate group, methacrylate group, vinyl group, alkenyl group bearing an unsaturated carbon at the chain end, or alkynyl group bearing an unsaturated carbon at the chain end.
2. The pneumatic tire according to claim 1 , wherein the crosslinkable resin is selected from the group consisting of vinyl ester resins.
3. The pneumatic tire according to claim 2 , wherein the crosslinkable resin is an epoxy vinyl ester resin based on novolac, bisphenol, or novolac and bisphenol.
4. The pneumatic tire according to claim 1 , wherein the i groups are each bonded to the X group through a heteroatom of the X group.
5. The pneumatic tire according to claim 1 , wherein the X group comprises at least one aromatic ring.
6. The pneumatic tire according to claim 5 , wherein the X group is an i-valent group having one of the formulae (II) to (IV):
in which the A 1 , A 2 and A 3 groups each represent, independently of one another, an at least divalent group comprising a heteroatom selected from oxygen and nitrogen.
7. The pneumatic tire according to claim 1 , wherein the X group is a trivalent group of formula (V):
8. The pneumatic tire according to claim 1 , wherein R is an acrylate, methacrylate, vinyl, allyl or ethynyl group.
9. The pneumatic tire according to claim 1 , wherein the crosslinking initiator is a radical initiator selected from the group consisting of halogenated compounds, compounds comprising an azo group, and peroxide compounds.
10. The pneumatic tire according to claim 1 , wherein the crosslinking initiator is a photoinitiator sensitive to UV above 300 nm.
11. The pneumatic tire according to claim 1 , wherein the crosslinking agent is a compound of formula (VI) or (VII):