聚偏氟乙烯PVDF是性能好的高分子制备薄膜材料，具有良好的热稳定性和耐腐蚀性。其应用广泛，常用语各种可溶性溶质的浓缩、分离等放慢，可同时用于液相和气相体系。但由于其又是疏水性材料，所以用其来制备膜会有易污染、寿命短等问题，因此浙大理工的沈同学对此进行了一番研究，做了聚偏氟乙烯PVDF超滤膜的制备与亲水性能检测实验，来分析各影响因素对PVDF膜的内部结构和关键性能的影响。
本期小潮主要是从对论文中实验过程中用到的检测仪器进行一番梳理，分享给需要进行聚偏氟乙烯PVDF性能类似研究的用户参考。聚偏氟乙烯PVDF超滤膜实验研究包括了制备以及亲水性能的改善测试，实验由三大部分组成，包括单因素实验、四因素五水平正交实验、增加膜的强度实验。
话不多说，进入主题，实验包括PVDF超滤膜的制备、水通量测定、接触角测定、平衡含水率测定、孔径测定、截留效果的表征、膜污染指数的测定、SEM电镜测试、膜的强度以及韧性的测定。那么需要用什么检测仪器来做对应的测试呢？见下表。
| 原料性能检测 - 光谱色谱 | |
 | 佑科 UV756 分光光度计 |
| 规格参数：光谱带宽2nm， 波长范围190~1100nm， 波长准确度±0.5nm， 波长重复性0.2nm， 杂散光0.05%T@220nm,360nm， 稳定性±0.001A/h@500nm， 数据接口USB接口， 透射比准确度±0.5%T， 透射比重复性0.2%T， 透射比测量范围0~200%T， 吸光度范围-0.30~3.0A， 浓度显示范围0~1999 | |
| 实验室通用设备 - 环境 | |
 | 荣华 76-1B 高精度玻璃恒温水浴槽 |
| Specification parameters: temperature control range RT+~100 (0.5 degrees), working tank size Ф300*300mm, total power 1000W, overall size 32*32*43cm | |
 | Huitai HWS-24 constant temperature Water Bath |
| Specification parameters: temperature control range RT+5~100°C, temperature fluctuation ±0.5°C, temperature resolution 0.1°C, working tank volume 9.9L, working tank size 300*300mm, working tank depth 110cm, temperature control mode PID instrument control Mode, pump circulation mode internal circulation, total power 1000W, timing range 1~9999min, power supply voltage AC 220V, 50Hz, external dimension 345*345*220mm, pump flow without pump, working tank size 300*300*110mm, cup hole Size Each hole has five circles, the minimum diameter is 30cm, and the maximum size is 115cm | |
| Raw Material Performance Testing - Surface Tension | |
 | Fangrui JCY-2 contact angle Tester |
| Specification parameters: camera system professional CCD digital camera + high-performance microscope lens, the highest resolution is 1280×1024, the way of taking pictures is single, continuous, the light source is continuously adjustable LED cold light source, the light is uniform, the outline of the captured image is clearer, Higher resolution, contact angle analysis methods θ/2 method, tangent method, automatic calculation or manual (correction) calculation, contact angle measurement range 0~180°, contact angle test resolution 0.01°, solid surface energy equal to one liquid Calculation of surface free energy, drop volume, and solid adhesion by two-liquid method, surface tension test method none, surface tension test range none, surface tension test resolution none, before and after sample stage displacement: 60mm; left and right 35mm; up and down 50mm , the sample table can be adjusted horizontally, the diameter is 90mm, the size of the sample table is 105×120mm, the maximum thickness of the sample is ≤35mm, the tilting platform measures the advancing/retreating angle, sliding angle, the sampling method is manual micro-sampler, the overall size is 525*160*470mm , net weight 12kg, power supply voltage 220V, 50HZ, power 0.2KW | |
| Membrane Proofing- Membrane | |
 | Domestic TBJ-B2-XB wire rod scraper integrated coating testing machine |
| 规格参数：涂布厚度0.01-10mm 刮刀可升降， 涂布速率2~200mm/s， 涂布幅面300*400mm（涂布长度0-400mm任意设置）， 涂布时间数显显示，不同速度，时间精度控制，， 涂布棒规格标配1根国产线棒和1根精度高达1μm的进口线棒， 涂布宽度300mm， 刮刀长度400MM材质/不锈钢， 电 源电压220V 50HZ 1700W， 机器体积626*410*520（长*宽*高）， 机器重量净重55KG， 速度控制无极变速， 底板材质玻璃， 可选附件漏液槽、基材固定夹具、微调水平高度支撑脚装置、玻璃板、硅胶垫和砝码（针对涂布基材厚度不均的应用）， 可定制功能 喷气系统装置、UV固含装置、自动加墨系统 | |
 | 圣恳 HLKGM3125 台式涂膜机 |
| 规格参数：涂布宽度250mm， 涂布行程310mm， 涂布速率0~10m/min， 涂布厚度范围25~3000μm， 总功耗300W， 主机电源AC200V， 外形尺寸680*370*380mm， 整机重量约40Kg， 刮刀与玻璃底板隔距隔距可调（数字显示）， 刮刀材质不锈钢SUS316L， 涂布底座尺寸350*300mm | |
| 环境测试 - 调温调湿 | |
 | 泰斯特 101-1AB 电热鼓风干燥箱 |
| Specification parameters: temperature control range RT+10~250°C, temperature fluctuation ±1.0°C, temperature resolution 0.1°C, temperature uniformity ±2.5%, volume 71L, studio size 450*350*450mm, studio material high-strength carbon Steel plate, shelves (standard) 2pcs, maximum number of shelves 13pcs, maximum load of a single shelf 15kg, timing range 0~9999 minutes (with timing waiting function), power supply voltage AC220V/7.3A 50/60Hz, input power 1.6KW , Dimensions 752*520*680mm, net weight 40kg, outer box material cold-rolled steel plate, surface chemical resistance coating, thermal insulation material aluminum silicate fiber, heater stainless steel heating tube, exhaust port inner diameter 28mm*2, rear Top test hole, thermostat digital tube double column PID, temperature setting method, touch four buttons to set, temperature display method, measurement temperature display: 4-digit digital upper display; set temperature display: 4-digit digital lower display , operation function fixed value operation, timing operation, automatic stop, optional program mode, additional function deviation correction, menu key lock, power failure compensation, power failure memory, temperature sensor pt100, outer packaging size 875*595*812mm, partition spacing 25mm , gross weight 50kg, 4 shelves (standard), optional accessories partition, RS485 interface, printer, Recorder, external communication, remote control, program temperature controller, wireless SMS alarm, U disk data storage | |
| General Laboratory Equipment - Quality | |
 | Huazhi PTX-JA1000 Analytical Balance |
| Specification parameters: Weighing range 1000g, minimum weighing value 1mg, readability accuracy 1mg, repeatability error ± 1mg, external calibration for calibration function, adjustable stabilization time, working conditions 10°C – 30°C, 80%RH, Non-condensing, weighing pan size Ф128mm, external dimension 345*223*331mm, data interface RS-232, display LCD large interface backlight display, bottom shell made of aluminum alloy, linear error ± 3mg | |
| General laboratory equipment - other | |
 | Shanghai Analysis SHB-IIIA Circulating Water Vacuum Pump |
| Specification parameters: power 180W, pumping rate 80L/min, head 10m, maximum vacuum degree -0.098Mpa (2Kpa), single head pumping rate 10L/min, number of pumping heads 2, safety function check valve, casing Material plastic, Water Tank volume 15L, Water Tank material PP, external dimensions 385*280*420mm, weight 11Kg, power supply voltage 1-110V, 60HZ or 220-240V, 50/60HZ | |
The above are the instruments used in this experiment and the corresponding technical parameters. After the results of this study, some research conclusions have also been drawn. The increase of PVDF concentration will reduce the water flux of polyvinylidene fluoride membrane, the rejection rate will increase, the contact angle will basically remain unchanged, the number of surface pores will decrease, and the thickness of the membrane will decrease. Ascending, internal finger-like structure decreases and spongy structure increases. In addition, when the concentration of PEG is 6wt%, the improvement of hydrophilicity is better. For more conclusions and a more detailed experimental process, you can read the original text of the paper, and the editor will not repeat it here.
