摘要淀粉是绿色植物光合作用的最终产物,是地球上由生物合成的最丰富的可再生资 源,具有资源丰富、品种繁多以及价格便宜的特点。
本论文将一定量的淀粉(疏水处理)、醋酸乙烯酯共聚物(EAA)、PBAT、增塑 剂及助剂,经共混机均匀共混,由双螺杆挤出机挤出切粒,并由粉碎机粉碎,用筛网 筛分出 2040 目的粒料备用。将所选粒料放入反应釜,并加入一定量的发泡剂和助剂, 设置一定的温度(85℃~90℃)和压力(0。8MPa),浸渍一定的时间(4h~6h)后,出 料,干燥,得预发泡颗粒,采用热空气法将预发泡料进行预发泡,制得预发泡粒料, 将预发泡粒料置于模压成型机中发泡成型制得淀粉基全生物降解发泡材料。通过采用4 因素 3 水平正交试验研究了发泡条件及工艺对发泡材料表观密度和泡孔形态的影 响,并研究了微孔发泡材料的微观结构及其压缩性能。结果表明,发泡剂投入量为 10%,浸渍时间为 5h,发泡温度为 180℃,发泡时间为 15min,是淀粉基全生物发泡 材料的最优发泡方案;淀粉基全生物降解发泡材料的压缩性能与泡孔均匀性及表观密 度相关,密度较小时,泡孔均匀性越好,压缩性能越好。95164
本文为淀粉基材料的发泡提供了一种新的发泡方法,制备出淀粉基全生物降解发 泡材料,为淀粉发泡的进一步研究提供理论参考。
毕业论文关键词:淀粉;PBAT;模压发泡;全生物降解发泡材料
Abstract Starch is the ultimate product of green plant photosynthesis and is the most abundant renewable resource on the planet by biosynthesis。 It is rich in resources, variety and cheap。 The main characteristics of starch is susceptible to microbial erosion, providing nutrients for microorganisms, with excellent biodegradability。 At the same time, its products can also overcome the polystyrene and other foam does not have the shortcomings of anti-static effect, more suitable for a variety of packaging and transportation。
In this paper, a certain amount of starch (hydrophobic treatment), vinyl acetate copolymer (EAA), PBAT, plasticizer and additives, were extruded by twin screw extruder after blending evenly, then pelletized and crushed。 Screening out 20 to 40 mesh pellets。 Set a suitable temperature (85℃ to 90℃) and pressure (0。8 MPa) ,a certain pellets was added to the reaction kettle with some blowing agents and the auxiliary agent 。 After a certain time(4h to 6h), taking out the pellets and drying, and the Impregnated pellets are used to pre-foam by hot air, then the expanded pellets are placed in a molding machine to prepare starch-based biodegradable foam material。 The effects of foaming conditions and process on the apparent density and cell morphology of the foaming materials were studied by using the 4-factor 3-level orthogonal test。 The microstructure and compressive properties of the microporous foaming materials were studied。The results show when the foaming agent is 10%, the immersion time is 5h, the foaming temperature is 180 ℃ and the foaming time is 15min, which is the optimal foaming scheme of starch - based bio - foaming material。The compressive properties of the starch-based biodegradable foaming material decrease with the increase of the apparent density of the material, Simultaneously, which is also related to the uniformity of the cell。 The more uniform the cell,and the better the compressive performance 。
Key words: Starch ; PBAT; Molding foaming; Biodegradable foamed material
目录
第一章 绪论 1
1。1 淀粉的简介 1
1。2 淀粉的应用技术及发展 1
1。2。1 颗粒淀粉