Eastman Tritan™ 코폴리에스터는 전자 빔 살균에 의해 어떠한 영향을 받나요?

의료 기기에 사용된 투명한 폴리머의 광학적 및 물리적 특성은 살균 과정에서 변형될 수 있습니다.
 
전자 빔 (e-빔) 방사선은 감마선, 에틸렌옥사이드(EtO), 오토클레이브, 저온 과산화수소 가스플라스마 등과 함께 의료 기기 살균에 많이 사용되고 있습니다.
 
Eastman은 e-빔 방사선이 Eastman Tritan 코폴리에스터와 다른 투명 의료 폴리머의 광학적 및 물리적 특성에 미치는 영향을 확인하기 위해 연구를 수행했습니다.
 
Formula Resin type
Eastman Tritan copolyester MX711 코폴리에스터
Eastar polyester MN052 polyester
Eastar copolyester MN211 코폴리에스터
Eastar copolyester MN006 코폴리에스터
DuraStar polymer MN611 코폴리에스터
Tenite propionate 360A40012 Cellulose acetate propionate (CAP)
Lipid resistant PC polycarbonate
TABS Transparent ABS
Medical grade acrylic Acrylic (PMMA)

The objective of sterilizing medical devices is to reduce the bioburden to a safe level with minimal effects on the desired properties of its constituent polymers.
 
Technology advances have improved the performance of e-beam radiation, making it a safe, efficient, and reliable source of energy for sterilization. High dose rates reduce the time of exposure, which can make e-beam a less costly alternative to gamma radiation.
 
To study the effect of e-beam radiation on Tritan MX711, Eastman measured color shifting and physical property retention after e-beam radiation.   

Optical properties
Samples were exposed to e-beam radiation (25 and 50 kGy), then stored in darkness and their color measured at Days 3, 7, 14, and 42 using HunterLab UltraScan Sphere 8000 and the CIE L*, a*, b* color scale. (Samples were stored in darkness and only exposed to light for color measurement.)
 
Figure 1 shows the changes in b* value, which measures the blue to yellow scale after e-beam exposure at 50 kGy. Photos of the molded samples before and after exposure are available upon request.

Figure 1. Eastman Tritan copolyester and other transparent resins after e-beam exposure at 50 kGY—b* color measurements




Figure 2 shows the difference in b* color values between unexposed samples and sterilized samples at Day 42—after e-beam radiation at both 25 and 50 kGy. 

Figure 2. Change in b* color 42 days after e-beam radiation—25 and 50 kGy  

Physical properties were measured before and after e-beam sterilization at 25 and 50 kGy. No physical property degradation was noted for Tritan MX711 or the other resins tested. The polyesters and copolyesters in the study showed no statistical change in molecular weight although Tenite propionate 360 did show a loss of molecular weight, as expected from an aliphatic polymer. 

For complete details of these studies or more information about the advantages of Eastman Tritan copolyesters, email Eastman today.