EFFECT OF ETHYLENE OXIDE STERILIZATION ON PLASTISIZER MIGRATION AND MECHANICAL AND BLOOD PROPERTIES OF MEDICAL GRADE POLYVINYLE CHOLORIDE

The use of phthalates as a plasticizer in plasticized polyvinyl chloride (PVC) always poses the threat of migration of phthalates into the environment through medical equipment. Phthalates can be used with natural-based plasticizers, such as Epoxidized soybean oil (ESBO) known as phthalate’s scavenger and PVC stabilizers. PVC formulations were characterized by different combinations of di (2-ethylhexyl) phthalate (DEHP) 30-40% with 5% ESBO. PVC flexibility increased significantly in the presence of ESBO, without a change in strength (tensile test). The decrease of the Tg temperature by adding ESBO in Differential Scanning Calorimetry indicated that ESBO preserved DEHP in the polymer. Also, it was shown that the sterilization process with Ethylene Oxide, similar to ESBO, decreased the Tg of polymer. DEHP migration was evaluated at a maximum level to the environment using the Gas Chromatography test. Samples containing ESBO showed less hemolysis. ABSTRAK: Penggunaan phthalates sebagai plasticizer dalam plastik polyvinyl chloride (PVC) selalu menimbulkan ancaman penghijrahan phthalates ke alam sekitar melalui peralatan perubatan. Phthalates boleh digunakan dengan plasticizer berasaskan semula jadi, seperti minyak kacang soya Epoxidized (ESBO) yang dikenali sebagai pemulung phthalate dan penstabil PVC. Formulasi PVC dicirikan oleh kombinasi yang berbeza di (2-ethylhexyl) phthalate (DEHP) 30-40% dengan 5% ESBO. Fleksibiliti PVC meningkat dengan ketara di hadapan ESBO, tanpa perubahan kekuatan (ujian tegangan). Penurunan suhu Tg dengan menambahkan ESBO dalam Calorimetri Pengimbasan Berbeza menunjukkan bahawa ESBO mengekalkan DEHP dalam polimer. Juga, ditunjukkan bahawa proses pensterilan dengan Etilena Oksida, serupa dengan ESBO, menurunkan Tg polimer. Penghijrahan DEHP dinilai pada tahap maksimum ke lingkungan menggunakan uji Kromatografi Gas. Sampel yang mengandungi ESBO menunjukkan kurang hemolisis.