Functionalized polymer particles for use as toughening agent
Composite materials and structural adhesives containing particles of functionalized polymers as a toughening agent. The particles are composed of functionalized polyaryletherketone (PAEK) polymer or copolymer thereof that contain chemical functional groups capable of reacting with a thermoset resin component to form covalent bonds.
1. A composite material comprising:
a curable thermoset matrix resin comprising at least one thermoset resin;
reinforcement fibers impregnated with the curable thermoset matrix resin;
particles of an amine-functionalized polyaryletherketone (PAEK) polymer or copolymer thereof,
wherein said amine-functionalized polyaryletherketone (PAEK) polymer or copolymer has a weight average molecular weight (Mw) of 26,000 to 162,000 as determined by gel permeation chromatography,
wherein the particles comprise amine functional groups on the particles that are capable of forming covalent bonds with the thermoset resin and the particles are substantially spherical in shape with an aspect ratio (R) of about 1 to about 1.5,
wherein the amine-functionalized PAEK polymer or copolymer has the following structure:
where E is an amine functional group and n is an integer from 15 to 200, and
wherein at least one of R1 and R3 is the branch unit:
and
the branched unit(s) is/are present in a molar percentage of 0.5% to 25%.
2. The composite material of claim 1 , wherein E is phenoxyaniline.
3. The composite material according to claim 1 , wherein said particles have an aspect ratio (R) of about 1.
4. The composite material according to claim 1 , wherein the particles have diameter of less than 75 μm.
5. The composite material according to claim 1 , wherein the at least one thermoset resin is selected from the group consisting of: epoxides, bismaleimide, and benzoxazine.
6. The composite material according to claim 1 ,
wherein the reinforcement fibers are arranged as a plurality of fibrous layers, and at least one interlaminar region is created between two adjacent fibrous layers, and
wherein the particles are positioned in the interlaminar region.
7. The composite material of claim 6 , wherein the reinforcement fibers in each fibrous layer are unidirectional fibers.
8. The composite material of claim 6 , wherein the reinforcement fibers in each fibrous layer are woven.