matrix (composite)

A matrix serves the following functions:{{Cite web|title=The matrix|url=https://www.compositesworld.com/articles/the-matrix|access-date=2020-12-16|website=www.compositesworld.com|language=en}}{{Cite web|title=Organic Matrix of Composite Materials|url=https://www.pfh-university.com/blog/organic-matrix-of-composite-materials.html|access-date=2020-12-16|website=www.pfh-university.com}}

• It binds the fiber reinforcement.
• It provides the composite component its shape and directs its surface quality.

Traditional materials such as glues, muds have traditionally been used as matrices for adobe and papier-mâché.

The common matrices are polymers (mainly utilized for fibre reinforced plastics). The most common polymer-based composite materials which include carbon fibre, fibreglass and Kevlar, typically involve two parts at least, the resin and the substrate.{{Cite web|title=5: Matrix Materials {{!}} School of Materials Science and Engineering|url=http://www.materials.unsw.edu.au/tutorials/online-tutorials/5-matrix-materials|access-date=2020-12-17|website=www.materials.unsw.edu.au}} Asphalt concrete, which is often used in the construction of roads, has a matrix called bitumen. Mud (wattle and daub) has observed considerable use.{{Cite web|last=Williams|first=Len|date=2018-09-14|title=Is it the end of the road for asphalt and concrete?|url=https://eandt.theiet.org/content/articles/2018/09/is-it-the-end-of-the-road-for-asphalt-and-concrete/|access-date=2020-12-17|website=eandt.theiet.org|language=en-US}}

Epoxy is utilized as a structural glue or structural matrix material in the aerospace industry. Epoxy resin is, when cured, nearly transparent.{{Cite web|title=Aerospace|url=https://epoxy-europe.eu/application/aerospace/|access-date=2020-12-17|website=Epoxy Europe|language=en-GB}}

Polyester resin is fit for most backyard projects. It tends to have a yellowish colour.{{Cite web|last=|first=|date=October 1999|title=Hazardous Substance Fact Sheet: Methyl Ethyl Ketone Peroxide|url=https://nj.gov/health/eoh/rtkweb/documents/fs/1259.pdf|archive-url=|archive-date=|access-date=Dec 17, 2020|website=New Jersey Department of Health}} It is often used in the construction of surfboards and for marine applications.{{Cite web|title=Polyester Resins|url=https://www.swindoncompositesupplies.co.uk/polyester-resins-2-c.asp|access-date=2020-12-17|website=www.swindoncompositesupplies.co.uk}} They are usually coated as they can tend to deteriorate over time and sensitive to ultraviolet. Peroxide is considered as the hardener of polyester resin. Mostly, MEKP (methyl ethyl ketone peroxide) is considered for polyester resin. A curing reaction is initiated when the peroxide is combined with the resin, and decomposes to generate free radicals. In these systems, often hardeners are called catalysts. But they do not meet the strictest chemical definition of a catalyst as at the end of the reaction they do not re-appear unchanged.{{cn|date=September 2021}}

Vinyl ester resin has a lower viscosity than polyester resin and is more transparent. It also tends to have a purplish to bluish to greenish tint. The price of the vinyl ester resin is similar to that of the polyester resin. It utilizes the same hardeners as polyester resin (at a similar mix ratio). It doesn't degrade much over time, when compared to polyester resin, and is more flexible. Generally, vinyl ester resin is considered as fuel resistant. However, it will melt when in contact with gasoline.{{Cite web|last=B. S.|first=Business Management|title=What are the Pros and Cons of Using Vinyl Ester and Polyester Resin|url=https://www.thoughtco.com/vinyl-ester-vs-polyester-resins-820376|access-date=2020-12-17|website=ThoughtCo|language=en}}

Shape memory polymer (SMP) resins are those materials that their shape and can be modified regularly by heating above their glass transition temperature (Tg). They become elastic and flexible when heated, allowing for easy configuration. They maintain their new shape when they are cooled. When they are reheated above their Tg, they will return to their original shape. The benefit of these resins is that without losing their material properties, they can be shaped and reshaped regularly. These resins can be utilized in making shape memory composites. Depending on their formulation, they have varying visual characteristics. These resins can be utilized in very cold temperature applications, such as for sensors that show whether perishable goods have warmed above a particular maximum temperature when they are acrylate-based; in space applications when they are cyanate-ester-based; in auto body and outdoor equipment repairs when they are epoxy-based.{{Cite web|title=Shape Memory Polymers {{!}} Sheffield Hallam University|url=https://www.shu.ac.uk/research/specialisms/materials-and-engineering-research-institute/what-we-do/expertise/shape-memory-polymers|access-date=2020-12-17|website=www.shu.ac.uk}}{{Cite web|last=www.technicaltextile.net|title=Features of Shape Memory Polymers (SPMS) - Properties of SPMS|url=http://www.technicaltextile.net/articles/new-purview-of-alacrity-shape-memory-polymers-smps-7492|access-date=2020-12-17|website=www.technicaltextile.net|language=EN}}

Cement (concrete), ceramics, sometimes glasses and metals are employed. Unusual matrices such as ice are sometimes proposed as in pykecrete.

{{reflist}}

Category:Composite materials