Carbon/graphite fiber reinforced poly(methyl methacrylate): Properties under dry and wet conditions

Abstract

The flexural properties of poly(methyl methacrylate) (PMMA) reinforced with carbon/graphite (C/G) fibers with three different surface treatments were investigated by transverse bend testing after dry and wet storage. The fibers used were (1) commercially available fibers, (2) cleaned fibers, and (3) cleaned and sized fibers. The coating agents of commercial unidirectional and braided C/G fibers as well as impurities on C/G fibers for medical uses were characterized by means of high-performance liquid chromatography (HPLC). The agar overlay technique was used to assess the cytotoxicity of leachable elements from different fibers and processed composites. Composites with both unidirectional and braided tubular C/G fibers were investigated after storage in water. Fracture stress and flexural modulus decreased when "commercial" fibers were used as reinforcing material. Composites with cleaned and sized fibers gave only minor differences in flexural properties after dry and wet storage. By means of SEM micrographs the adhesion behavior of unsized C/G fibers, epoxy sized fibers, cleaned fibers, and cleaned and sized fibers were assessed. After water storage a substantial part of the cleaned fibers adhered to the matrix material. The adhesion capacity of the other fibers was reduced since the water absorption caused separation of fiber and matrix.

Fatigue of Restorative Materials

“…Factors affecting mechanical properties include the types of fibers used (DeBoer et al, 1984;Mullarky, 1985;Ekstrand et al, 1987;Berrong et al, 1990;Gutteridge, 1992;Vallittu and Docent, 1999), the direction and pattern design of the fiber reinforcement (Vallittu, 1998;Rudo and Karbhari, 1999;Vallittu and Docent, 1999), and uniform pre-impregnation (wetting) of the fiber with resin (Vallittu, 1995;Vallittu and Docent, 1999). Silanated glass fibers are often used because of the well-documented good adherence of treated glass fibers to the polymer matrix, thereby facilitating stress transfer from matrix to fiber and improved esthetics (Takagi et al, 1996).…”

Reinforcing effects of different fibers on denture base resin based on the fiber type, concentration, and combination

“…Various types of fibers such as carbon, glass, polyaromatic polyamide (aramid), and ultra-high molecular weight polyethylene (UHMWP) have been studied [12][13][14][15][16] . Carbon fibers have been effective in reinforcing denture base resin, but their dark color is unaesthetic, and they are difficult to polish 12,14,17) . However, glass fibers are aesthetically stable, and improve the flexural and impact strength of denture base resins 13,18) .…”

Flexural properties of ethyl or methyl methacrylate-UDMA blend polymers

“…There are several attempts [3][4][5][6][7][8][9][10][11][12][13][14][15][16] to increase the mechanical properties of denture base resins. One approach is to devise a reinforcement of denture base polymer with fibers, chips, or rods [12][13][14][15][16] . This technique is effective to improve the mechanical properties; however it is very difficult to incorporate accurately reinforcing materials in the desired position of the denture base resin.…”

“…Many attempts to improve the mechanical properties of polymethyl methacrylate (PMMA) have included using alternate polymers such as polycarbonate 3) , nylon 4,5) , copolymers 6,7) and urethane dimethacrylate (UDMA) 8,9) , and incorporating of butadiene-styrene rubber into PMMA matrix 10,11) . As another attempt, various fiber or chip materials [12][13][14][15][16] such as carbon, aramid and glass have been added into PMMA resin for reinforcing materials, and metal wires and meshes have ordinary been used for reinforcing materials to prevent the midline fracture of denture.…”