The fibrillation of cellulose from eucalyptus kraft pulp was obtained by oxidation treatment with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) as chemical pretreatment at pH 10. The chemically-treated cellulose was followed by mechanical treatments such as ultrafine grinding or high-pressure homogenization treatments to yield nanofibrillated cellulose (NFC). The morphology, carboxyl group content, and rheological properties of the prepared NFC were measured. Poly(vinyl alcohol) (PVA) composite films containing small amount of NFC were prepared and the optical and mechanical properties of the films were evaluated. The fiber thickness of NFC decreased with increasing pass number of mechanical treatments. The mechanical properties of the PVA/NFC composite films were the best at 0.05 wt% of NFC content. The film showed small decrease in the optical transmittance with increase in the added amount of NFC.

Eucalyptus 크라프트 펄프를 2,2,6,6-tetramethyl-1-piperidinyloxy(TEMPO)로 처리하여 셀룰로오스를 부분 산화시킨 후, 초미세분쇄기, 고압 균질화기 등의 기계적 처리로 나노피브릴화 셀룰로오스(NFC)를 제조하였다. NFC의 형태, 카복시기 함량, 유변학적 특성 등을 측정하였으며, NFC가 소량 혼합된 PVA 복합필름을 제조하여 광학적 특성과 기계적 성질 등을 평가하였다. 나노피브릴화 셀룰로오스의 섬유직경은 기계적 처리 횟수가 증가함에 따라 감소하였다. PVA/NFC 복합필름의 기계적 특성은 NFC 함량 0.05 wt%에서 가장 우수하였으며, 극소량의 NFC의 첨가로도 필름의 기계적 특성은 상당한 수준으로 향상되었으며, NFC 첨가에도 불구하고 PVA 필름의 광투과도의 손실은 크지 않았다.

Keywords: nanofibrillated cellulose, TEMPO-oxidation, ultrafine grinder, high-pressure homogenizer, PVA film.