羧甲基纤维素与短切稻草的热压复合研究

为了探索新的稻草利用途径,开发一种基于稻草的环保复合材料,对羧甲基纤维素与稻草的热压复合进行了研究。将稻草进行短切,以水为混合及复合助剂,先使羧甲基纤维素与稻草在常温常压下进行混合,然后在热压机上进行加热加压复合。研究了羧甲基纤维素用量、热压温度、热压时间对复合材料拉伸力学性能及硬度的影响。结果表明,复合材料的拉伸强度随羧甲基纤维素的用量的增加而增加,随热压时间及热压温度的增加先增加后减小,在羧甲基纤维素用量50%,热压温度120℃,热压时间10 min时,复合材料的拉伸强度为1.52 MPa。复合材料的硬度受加工条件的影响较小。     

淀粉/茅草复合材料的热压制备工艺研究

探索制备淀粉/茅草复合材料的制备工艺条件,以便开发新型的可降解复合材料。以淀粉为黏结剂、茅草颗粒为主要原料,水作为塑化剂,用热压成型的方法制备了淀粉/茅草复合材料;测试了复合材料的硬度、拉伸强度和扯断伸长率等力学性能;讨论了黏结剂用量、塑化剂-水的用量对复合材料力学性能的影响。淀粉含量为40%(干基)、水用量为25%(湿基)、热压温度120℃、热压时间10min时,制备的淀粉/茅草复合材料的拉伸强度和扯断伸长率最高,硬度稍低。     

PVA/CMC复合膜的制备及其渗透汽化特性研究

制备了ＰＶＡ（聚乙烯醇）／ＣＭＣ（羧甲基纤维素）渗透汽化复合膜。研究了ＰＶＡ／ＣＭＣ用量比、交联剂用量、乙醇浓度、渗透汽化时间等因素对膜的渗透汽化性能的影响。发现ＰＶＡ／ＣＭＣ复合膜对８５－９８．３ｗｔ％乙醇溶液表现为水优先透过。在２６．５°Ｃ和１ａｔｍ下,９０．８ｗｔ％乙醇溶液渗透汽化３小时、膜内乙醇浓度增至９８．３ｗｔ％。达到了较好的醇／水分离效果     

聚苯胺/碳复合材料制备研究

聚苯胺/碳复合材料是一种优良的导电材料,用原位聚合法制备了聚苯胺/碳复合材料,对聚合工艺的研究表明聚合条件为:聚合温度:19~20℃;聚合时间在14h;An/C质量比为1∶1。最佳碳基体:1000SF60时电导率最佳。     

碳纳米管/聚合物复合材料的制备研究

介绍了碳纳米管的结构和特性,着重对碳纳米管/聚合物纳米复合材料的制备方法、研究新动向以及该研究领域所面临的一些问题进行了综述。     

稻草制羧甲基纤维素钠的研究

介绍以稻草为原料制备羧甲基纤维素纳的工艺条件。实验得出稻草纤维素醚化反应的最佳条件是：稻草纤维素钠、氢氧化钠、一氯乙酸的物料比为8∶3.5∶3；溶剂乙醇的含水量为30％；在70℃条件下反应5小时．纤维素醚化度可达0．8以上，是水溶性较好的纤维素钠．     

高沸醇法(HBS法)制备稻草纸浆和木质素

采用1，4—丁二醇水溶液为溶剂的高沸醇溶剂法，从稻草中制备纤维素与木质素。在1，4—丁二醇水溶液中添加少量助剂、并在190℃—220℃条件下蒸煮1—3小时的方法制得纸浆和木质素。制得的纸浆可用于造纸。不溶于水的高沸醇(HBS)木质素则可以通过加水沉淀的方法，从反应后的液体混合物中分离。HBS木质素具有较高的反应活性，通过进一步改性，还有更多潜在的应用价值。回收的高沸醇溶剂，可作为制浆溶剂循环使用。     

纳米金刚石/CaCO3/PP复合材料制备及力学性能研究

以俄罗斯生产的纳米金刚石为改性剂,采用熔体共混法制备了纳米金刚石/CaCO3/聚丙烯树脂(PP)复合材料,探讨了纳米复合材料的分散工艺及不同纳米金刚石含量对复合材料力学性能的影响.实验结果表明:适量添加纳米金刚石可提高PP复合材料各种力学性能;纳米金刚石用量(质量分数)为4%时,PP复合材料抗压强度达34.431 MPa,比纯PP复合材料提高20%,冲击强度提高66%,抗拉强度提高39%.     

复合材料热压罐成型工艺实验教学探讨

通过复合材料热压罐成型工艺实验,让学生实践原材料—工艺—性能关系的复合材料制备全过程,掌握湿法制备预浸料与热压罐成型工艺的基本实验技能,同时学生自主设计实验方案,激发其综合运用课堂理论知识。实验课程内容对于学生理解复合材料热压罐成型工艺的原理和复合材料的复合效应、性能的可设计性、构件与材料同步性等具有重要意义。     

PP/MMT复合材料的制备及性能研究

采用甲基丙烯酸甲酯(MMA)与PP接枝共聚物(PP-g-MMA)为界面相容剂,在熔融共混的条件下;利用螺杆挤出机制备PP/MMT复合材料,对其流动性能及力学性能进行了研究.结果表明:PP-g-MMA的加入提高了PP与O-MMT的相客性,当PP-g-MMA用量为20wt%,O-MMT的用量为3wt%时,力学性能最佳:拉伸强度提高了17.46%;常温下冲击强度提高了91.05%;低温(-20℃)条件下的冲击性能比常温下提高了40.29%,比低温下的纯PP提高了246.78%.     

Miscibility on blends of PVA and PFSA by viscometry

The intrinsic viscosity and viscometric interaction parameters of perfluorosulfonic acid(PFSA) and poly(vinyl alcohol)(PVA) were measured by dilute solution viscometry.The miscibility between PFSA and PVA was estimated by the criteria of △B and μ.The results indicated that PFSA and PVA were completely miscible for any weight fraction in aqueous solution.     

PVA纤维静电纺丝工艺参数研究及正交设计优化

采用静电纺丝法制备聚乙烯醇（PVA）超细纤维膜,利用扫描电子显微镜（SEM）观察溶液浓度、纺丝电压、纺丝距离对纤维微观形貌的影响,并采用正交设计对纺丝工艺参数进行优化。实验结果表明:纺丝电压是影响纤维平均直径的最重要的参数。经过优化,纺制出最小直径为0.27μm的PVA超细纤维。     

用于乙醇-水分离的SA-PVA/PSF中空纤维渗透汽化复合膜

Using polysulfone (PSF) hollow fiber ultrafiltration membranes as the substrate, sodium alginate (SA) and polyvinyl alcohol (PVA) blend solutions as the coating solution, and maleic anhydride (MAC) as the cross-linked agent, SAPVA/PSF hollow fiber composite membranes were prepared for the dehydration of ethanol-water. The effects of different sodium alginate concentration in the coating solutions and different operating temperatures on pervaporation performance were investigated. The experimental results showed that pervaporation performance of the SA-PVA/PSF composite membranes for ethanol-water solution exhibited a high separation factor although they had a relatively low permeation flux. As SA concentration in SA-PVA coating solution was 66.7% and the operating temperature was 40 ℃, SA-PVA/PSF hollow fiber composite membrane (PS4) had a separation factor of 886 and flux of 12.6 g/(m2·h). Besides, SA-PVA/PSF hollow fiber composite membranes (PS3 and PS4) were used for the investigation of the effect of ethanol concentration in the feed solution on pervaporation performance.     

Enhancement of durability of glass fiber-reinforced cement with PVA

The main thrust of this research was to determine the effectiveness of polyvinyl alcohol (PVA) powder in enhancing the durability of short GFRC materials. Accelerated aging of the materials was achieved through low-pressure steam curing in a moist chamber. The strength and ductility of GFRC were measured by the direct tension test, which showed that incorporation of PVA powder into GFRC could improve its mechanical behaviour and turn it from brittle to ductile. To investigate the mechanism of the tensile strength enhancement, the fiber-matrix interface was examined by polarizing optical microscopy and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDAX). It was found that PVA powder tended to migrate to the fiber-matrix interfacial zone and thus prevented the accumulation of calcium hydroxide in this area. PVA film around the fiber resulted in a more ductile interfacial microstructure and better bonding between fiber and matrix, which should be responsible for enhancing the tensile property and preventing the aging of GFRC. Furthermore, PVA powder reduced the microhardness and brittleness at the interface.     

Simultaneous removal of cadmium and sulfamethoxazole from aqueous solution by rice straw biochar

The simultaneous sorption behavior and characteristics of cadmium (Cd) and sulfamethoxazole (SMX) on rice straw biochar were investigated. Isotherms of Cd and SMX were well modeled by the Langmuir equation (R2 >0.95). The calculated maximum adsorption parameter (Q) of Cd was similar in single and binary systems (34129.69 and 35919.54 mg/kg, respectively). However, the Q of SMX in a binary system (9182.74 mg/kg) was much higher than that in a single system (1827.82 mg/kg). The presence of Cd significantly promoted the sorption of SMX on rice straw biochar. When the pH ranged from 3 to 7.5, the sorption of Cd had the characteristics of a parabola pattern with maximum adsorption at pH 5, while the adsorption quantity of SMX decreased with increasing pH, with maximum adsorption at pH 3. The amount of SMX adsorbed on biochar was positively correlated with the surface area of the biochar, and the maximum adsorption occurred with d 250 biochar (biochar with a diameter of 150-250 μm). Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) showed that the removal of Cd and SMX by rice straw biochar may be attributed to precipitation and the formation of surface complexes between Cd or SMX and carboxyl or hydroxyl groups. The results of this study indicate that rice straw biochar has the potential for simultaneous removal of Cd and SMX from co-contaminated water.     

循环经济视角下秸秆禁烧问题研究——以安徽近几年秸秆禁烧工作为例

根据秸秆禁烧工作研究,分析当前秸秆禁烧和综合利用中存在的问题。结合安徽省实际,从循环经济视角下提出多渠道筹资调动积极性和"联收联耕"规避劳动力不足等措施。     

聚乙烯醇-羧甲基葡甘聚糖肥料包膜的制备及性能

以羧甲基葡甘聚糖和聚乙烯醇为原料,通过溶液共混、交联制备了新型肥料包膜.利用红外光谱表征了交联包膜的结构,并测试了包膜的吸水率和膜中尿素的释放性能.结果表明:包膜内聚乙烯醇、羧甲基葡甘聚糖和尿素之间产生了较强的相互作用,包膜内尿素具有一定的缓释性.     

膨润土复合无机高分子絮凝剂的制备及其在淀粉废水处理中的应用

以天然无机高分子材料膨润土为原料,应用化学改性方法,制备了膨润土复合无机高分子絮凝剂和自配膨润土复合无机高分子絮凝剂,并将其应用于淀汾废水处理,取得了较好效果,处理后的淀粉废水清澈透明,由实验可以得出结论淀粉废水中悬浮物COD的去除,受溶液的pH值影响较明,pH值越低效果越好.     

异丁醇直接电解氧化合成异丁酸异丁酯的研究

在酯化催化剂（H2SO4）作用下．异丁醇在Pb-PbO2阳极上电解氧化直接合成异丁酸异丁酯．考察了电极、温度、通电量及异丁醇浓度对产率的影响。