State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China.
State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China.
Int J Biol Macromol. 2020 Nov 1;162:678-684. doi: 10.1016/j.ijbiomac.2020.06.101. Epub 2020 Jun 13.
In this work, we prepared novel cellulosic paper by incorporating tannin into the kraft pulp for potential application in active food packaging. The kraft pulp fibers were firstly periodate oxidized to obtain the dialdehyde cellulosic fibers, and then reacted with varied dosages of tannin to incorporate them into the fibers by covalent bondings between aldehyde groups on cellulose and active hydrogen on tannin. Handsheets were prepared using the tannin incorporated fibers through papermaking process and the properties were characterized. The percentage of tannin in the paper increased with the increase of the tannin dosage. FT-IR spectra confirmed the successful incorporation of tannin into the cellulosic fibers. It was found that paper after incorporation of tannin turned to be surface hydrophobic with contact angles higher than 90°, which may probably due to the covalent bonds between tannin and cellulose. The handsheets show high antioxidative and UV-shielding properties, which both increased with the increase of the tannin percentage in the paper. Water vapor transmission rate (WVTR) decreased after the incorporation of tannin, and this could facilitate its application in food packaging. The breaking length of tannin incorporated paper decreased insignificantly, less than 10% with the tannin percentage as high as 45%.
在这项工作中，我们通过将单宁酸掺入牛皮纸浆中，制备了新型的纤维素纸，用于潜在的活性食品包装应用。首先将牛皮纸浆纤维进行高碘酸盐氧化，得到二醛纤维素纤维，然后用不同剂量的单宁酸与纤维反应，通过纤维素上的醛基与单宁酸上的活泼氢之间的共价键将单宁酸结合到纤维中。通过造纸工艺用掺入单宁酸的纤维制备手抄片，并对其性能进行了表征。纸中单宁酸的百分比随单宁酸用量的增加而增加。傅里叶变换红外（FT-IR）光谱证实了单宁酸成功掺入到纤维素纤维中。结果发现，掺入单宁酸后的纸张表面变得疏水，接触角高于 90°，这可能是由于单宁酸和纤维素之间形成了共价键。手抄片表现出高的抗氧化和遮光性能，这两种性能都随纸中单宁酸百分比的增加而增加。掺入单宁酸后，水蒸气透过率（WVTR）降低，这有助于其在食品包装中的应用。掺入单宁酸的纸张的抗张强度下降不明显，即使单宁酸的百分比高达 45%，也不到 10%。
