柑橘皮纤维素/聚磷酸铵/三聚氰胺/聚乙烯醇复合膜的制备及其性能

Preparation and Properties of Citrus Peel Cellulose/Ammonium Polyphosphate/Melamine/Polyvinyl Alcohol Composite Membrane

柑橘皮经酸解、碱解制得微晶纤维素(MCC),MCC协同聚磷酸铵(APP)、三聚氰胺(MA)作为聚乙烯醇(PVA)的改性材料,采用溶液共混、流涎成膜制得MCC/APP/MA/PVA的复合材料,考察了MCC/APP/MA(MAM)的用量及改性对复合材料性能的影响。用红外光谱(FTIR)、差示扫描量热仪(DSC)、热重分析仪(TG)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)等对复合材料性能进行表征和分析。FTIR显示柑橘皮中木质素、果胶等物质大部分已被有效去除,MCC成功制得。TG、DSC分析表明,当MAM质量分数为17%时,PVA/MAM的复合材料热稳定性最好;添加MAM后使复合材料的力学性能下降,用硅烷偶联剂对MAM改性,可以使复合材料的力学性能提高;XRD显示在MAM添加量少时,晶型与PVA相同,到29%时纤维素的晶型显示出来,同时形成一新的晶型;MAM含量为17%时复合材料,表面光滑,无孔洞;而MAM的含量为29%时,孔洞较多,有团聚现象。

Microcrystalline cellulose(MCC)was prepared by the acid hydrolysis and alkali hydrolysis of citrus peel.Taking ammonium polyphosphate(APP)and melamine(MA)as the modification material,MCC/APP/MA/polyvinyl alcohol(PVA)composite material was prepared by solution blending and salivation.The influence of amount and modification of MCC/APP/MA(MAM)on composite material properties were investigated.The properties of the composites were characterized and analyzed by fourier transform infrared spectrometer(FTIR),differential scanning calorimeter(DSC),thermogravimetric analyzer(TG),scanning electron microscope(SEM)and X-ray diffraction(XRD).The FTIR results show that most of lignin and pectin in citrus peel have been effectively removed,and MCC is successfully prepared.TG and DSC analysis show when MAM content is 17%,the thermal stability of PVA/MAM composite is the best.The mechanical properties of PVA/MAM composites decrease after adding MAM,and which are improved by modifying MAM with silane coupling agent.XRD results show when MAM content is low,the crystalline form is the same with PVA.When MAM content is 29%,the crystal form could be revealed.When the crystal of MAM is 17%,the surface of the composites is smooth and there are no holes.While the content of MAM is 29%,there are more holes and agglomeration.