[Influence of sterilization treatments on continuous carbon-fiber reinforced polyolefin composite].
OBJECTIVE
To evaluate the influence of sterilization treatment on continuous carbon-fiber reinforced polyolefin composite (CFRP) so as to provide experimental reference for selection of sterilization method for CFRP.


METHODS
Seventy bars of CFRP were divided into 7 equal groups to undergo sterilization by autoclave, 2% glutaraldehyde soaking, 75% alcohol soaking, ethylene oxide sterilization, and Co-60 gamma ray irradiation of the dosages 11 kGy, 25 kGy, and 18 kGy respectively, and another 10 bars were used as blank controls. Then the bars underwent three-point bending test and longitudinal compression test so as to measure the biomechanical changes after sterilization treatment, including the maximum load, ultimate strength, and elastic modulus.


RESULTS
Three-point bending test showed that the levels of maximum load of the all experimental groups were lower than that of the control group, however, only those of the 3 Co-60 irradiation groups were significantly lower than that of the control group and that Co-60 radiation lowered the level of maximum load dose-dependently; and that the levels of ultimate strength of all the all experimental groups were lower than that of the control group, however, only those of the 3 Co-60 groups were significantly lower than that of the control group and that the higher the dosage of Co-60 radiation the lower the level of ultimate strength, however, not dose-dependently. The elastic modulus of the Co-60 25 KGy group was significantly higher than that of the control group, and there was no significant difference in the level of ultimate strength among the other groups. Longitudinal compression test showed that the levels of maximum load and ultimate strength of the 3 Co-60 irradiation groups, autoclave group, and circular ethylene groups were significantly lower than that of the control group, and there was no significant difference in elastic modulus among different groups.


CONCLUSIONS
During sterilized package of CFRP products produced in quantity autoclave sterilization and Co-60 gamma ray irradiation sterilization should be avoided. Ethylene oxide is proposed as the best sterilization method. If gamma ray irradiation is to be used further technology improvement is necessary.
Guan
Shi-bing
SB
Department of Orthopedic Surgery, Second Affiliated Hospital of Shandong University, Jinan, China.
Hou
Chun-lin
CL
Chen
Ai-min
AM
Zhang
Wei
W
Wang
Ji-e
JE
D000438:Alcohols; D002244:Carbon / Q000592:standards*; D000077482:Carbon Fiber; D003037:Cobalt Radioisotopes; D005027:Ethylene Oxide; D005976:Glutaral; D006358:Hot Temperature; D008422:Materials Testing / Q000379:methods*; D010969:Plastics / Q000592:standards*; D011090:Polyenes / Q000592:standards; D015203:Reproducibility of Results; D013242:Sterilization / Q000295:instrumentation / Q000379:methods* / Q000592:standards
D000438:Alcohols; D000077482:Carbon Fiber; D003037:Cobalt Radioisotopes; D010969:Plastics; D011090:Polyenes; C037808:plastic, carbon fiber reinforced; D002244:Carbon; D005027:Ethylene Oxide; D005976:Glutaral