Fiber-reinforced composite articles made from fibers having coupling-initiator compounds and methods of making the articles

A fiber-reinforced composite article comprising:

• a thermoplastic polymer matrix;
• and
• fibers bonded to the thermoplastic polymer matrix by a reacted coupling-initiator compound coupled to the fibers prior to contact with thermoplastic polymer matrix, wherein the coupling-initiator compound initiated the polymerization of the thermoplastic polymer, and the coupling-initiator compound has the formula:
• S—X—(I)n
• wherein:
• n is an integer having a value between 1 and 5,
• S comprises a silicon-containing coupling moiety through which the coupling-initiator compound bonds to a substrate surface on the fibers,
• X comprises a linking moiety to link the S moiety with the one or more I moieties,
• (I)n comprises one or more polymerization initiator moieties,
• each of the initiator moieties is capable of initiating a polymerization of the monomer at the polymerization temperature, and
• each of the initiator moieties is the same or different.

A process for preparing a reinforced resin material comprising the steps of:

• providing an inorganic substrate;
• applying to the inorganic substrate a sizing composition comprising a coupling activator compound of the formula:
• wherein:
• X and Y comprise linking moieties to link the S moiety with the I moiety, and
• R3, R4, and R5 are the same or different, and are selected from the group consisting of an alkyl group, an aryl group, an alkoxy group, a halogen group, and an alkylcyclic group;
• mixing the sized inorganic substrate with a monomer and a polymerization catalyst to form a polymerization mixture;
• and
• exposing the polymerization mixture to conditions sufficient to cause polymerization of the monomer to form a reinforced resin in which the inorganic substrate is coupled to the surrounding polymer matrix.

A method of making a fiber-reinforced composite article, the method comprising:

• providing a pre-polymerized fiber-containing material comprising fibers in contact with a combination of a monomer and polymerization catalyst, wherein the fibers have been treated with a coupling-initiator compound;
• applying the pre-polymerized fiber-containing material to an article template;
• heating the pre-polymerized fiber-containing material to a polymerization temperature where the monomers polymerize around the fibers to form at least a portion of the composite article;
• and
• wherein the coupling-initiator compound has the formula:
• S—X—(I)n
• wherein n is an integer having a value of 2 or more;
• S comprises a silicon-containing coupling moiety through which the coupling-initiator compound bonds to a substrate surface on the fibers;
• X comprises a linking moiety to link the S moiety with the 2 or more I moieties;
• and
• (I)n comprises 2 or more polymerization initiator moieties, wherein each of the initiator moieties is capable of initiating a polymerization of the monomer at the polymerization temperature, and wherein each of the initiator moieties is the same or different.

A method of making a fiber-reinforced composite article, the method comprising:

• providing a pre-polymerized fiber-containing material comprising fibers in contact with a combination of a monomer and polymerization catalyst, wherein the fibers have been treated with a coupling-initiator compound;
• applying the pre-polymerized fiber-containing material to an article template;
• heating the pre-polymerized fiber-containing material to a polymerization temperature where the monomers polymerize around the fibers;
• removing the composite article from the article template;
• and
• wherein the coupling-initiator compound has the formula:
• S—X—(I)n
• wherein n is an integer having a value of 2 or more;
• S comprises a silicon-containing coupling moiety through which the coupling-initiator compound bonds to a substrate surface on the fibers;
• X comprises a linking moiety to link the S moiety with the 2 or more I moieties;
• and
• (I)n comprises 2 or more polymerization initiator moieties, wherein each of the initiator moieties is capable of initiating a polymerization of the monomer at the polymerization temperature, and wherein each of the initiator moieties is the same or different.