Mechanical and physical properties of carbon-graphite fiber-reinforced polymers intended for implant suprastructures.
OBJECTIVE
Mechanical properties and quality of fiber/matrix adhesion of poly(methyl methacrylate) (PMMA)-based materials, reinforced with carbon-graphite (CG) fibers that are able to remain in a plastic state until polymerization, were examined.


METHODS
Tubes of cleaned braided CG fibers were treated with a sizing resin. Two resin mixtures, resin A and resin B, stable in the fluid state and containing different cross-linking agents, were reinforced with CG fiber loadings of 24, 36, and 47 wt% (20, 29, and 38 vol.%). In addition, resin B was reinforced with 58 wt% (47 vol.%). After heat-polymerization, flexural strength and modulus were evaluated, both dry and after water storage. Coefficient of thermal expansion, longitudinally and in the transverse direction of the specimens, was determined. Adhesion between fibers and matrix was evaluated with scanning electron microscopy (SEM).


RESULTS
Flexural properties and linear coefficient of thermal expansion were similar for both fiber composites. With increased fiber loading, flexural properties increased. For 47 wt% fibers in polymer A the flexural strength was 547.7 (28.12) MPa and for polymer B 563.3 (89.24) MPa when water saturated. Linear coefficient of thermal expansion was for 47 wt% CG fiber-reinforced polymers; -2.5 x 10(-6) degrees C-1 longitudinally and 62.4 x 10(-6) degrees C-1 in the transverse direction of the specimens. SEM revealed good adhesion between fibers and matrix. More porosity was observed with fiber loading of 58 wt%.


CONCLUSIONS
The fiber treatment and the developed resin matrices resulted in good adhesion between CG fibers and matrix. The properties observed indicate a potential for implant-retained prostheses.
Segerström
Susanna
S
NIOM, Nordic Institute of Dental Materials, Postboks 70, N-1344 Haslum, Norway.
Ruyter
I Eystein
IE
D002244:Carbon / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003432:Cross-Linking Reagents / Q000737:chemistry; D001840:Dental Bonding; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry*; D004548:Elasticity; D005026:Ethylene Glycols / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D020366:Methylmethacrylate / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D018583:Pliability; D011108:Polymers / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011143:Polyvinyl Chloride / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D016062:Porosity; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D014867:Water / Q000737:chemistry
D003432:Cross-Linking Reagents; D015921:Dental Implants; D003764:Dental Materials; D005026:Ethylene Glycols; D008689:Methacrylates; D011108:Polymers; D011109:Polymethacrylic Acids; D011145:Polyvinyls; D014867:Water; D020366:Methylmethacrylate; C024546:diethylene glycol dimethacrylate polymer; C013215:polyvinyl acetate; D002244:Carbon; D006108:Graphite; C004919:ethylene dimethacrylate; D011143:Polyvinyl Chloride; D019904:Polymethyl Methacrylate; C102737:1,4-butanediol dimethacrylate