一、 材料表面润湿的原理 Principle of material surface wetting

薄膜材料中所谓润湿性， 这就是诸如水， 油墨、 粘合剂、 涂料等对塑料薄膜、纸张或金属箔附着的基础。 润湿性决定一种液体在一种固体表面上的展延性。 如水在亲水性表面就展延成一薄水层， 而在亲油性表面却形成小水滴。 水滴外表层的切线与固体表面间所形成的接触角（图1， 夹角θ） ， 即表示该表面润湿性能的强弱， 接触角越大， 润湿性能越差。物理界关于润湿的严格热力学定义是： 固体与液体接触后， 体系（固体十液体） 的自由焓降低时， 称为润湿。

Membrane material in the so-called wettability, this is such as water, ink, adhesives, coatings to plastic film, paper or metal foil adhesion basis. Wettability determines the ductility of a liquid over a solid surface. For example, water spreads out into a thin layer on a hydrophilic surface, but forms droplets on an oleophobic surface. The contact Angle formed between the tangents of the outer surface of the water drop and the solid surface (Figure 1, Angle θ), that is the wettability of the surface. The larger the contact Angle is, the worse the wettability is. In the physical , the strict thermodynamic definition of wetting is: after contact between a solid and a liquid, the enthalpy of the system (solid and liquid) decreases, which is called wetting.

图1  固体－液体相面润湿张力示意图

如上图， 考查其物理模型， 从热力学观点看， 当液滴落在一个清洁平滑的固体表面上，忽略液体的重力和粘度影响时，则液滴在固体表面上的铺展是由固-气（SV）、固-液（SL） 和液-气（LV） 三个界面张力所决定的， 其平衡关系如下确定：

As shown in the figure above, the physical model is examined. From the thermodynamic point of view, when the droplet falls on a clean and smooth solid surface, ignoring the effects of gravity and viscosity of the liquid, the droplet spread on the solid surface is determined by three interfacial tensions: solid-gas (SV), solid-liquid (SL) and liquid-gas (LV). The equilibrium relationship is determined as follows

γSV=γSL+γLV cosθ

F=γLV cosθ=γSV-γSL+γLV

式中： θ是润湿角， F 是润湿张力， γ是界面能。 显然， 当θ＞90° 则因润湿张力小而不润湿； θ＜90° 则润湿； 而在θ=0° 时， 润湿张力 F 最大， 可以完全润湿， 即液体在固体表面上自由铺展。 （产生界面能γ的主要原因是范德华力、 化学键力等在界面处不平衡导致的。这些作用力在固体的内部因为对称，相互抵消，在界面处因为无法对称， 从而显示了界面作用力， 即界面能） 。 可以看出， 达到我们所说的润湿先决条件是γSV＞γSL ， 或者γSL 十分微小。所以如果要达到疏油效果， 意味着接触角要越大越好， 张力越小越好；

Where, θ is the wetting Angle, F is the wetting tension, and γ is the interfacial energy. Obviously, when θ > 90°, the wetting tension is small and does not moisten. θ < 90° is wet; When θ=0°, the wetting tension F reaches its maximum and can be fully wetted, that is, the liquid spreads freely on the solid surface. (The main cause of interfacial energy γ is the imbalance of van der Waals forces and chemical bond forces at the interface. These forces cancel each other out because they are symmetrical inside the solid, and they cannot be symmetrical at the interface, thus showing the interface force, namely the interface energy). And you can see that the prerequisite for what we call wetting is gamma SV > gamma SL, or gamma SL is very small. So if you want to achieve the effect of oil drainage, it means that the larger the contact Angle, the better, the smaller the tension;

二、 常见塑料的表面张力（文献记录）Surface Tension of Common Plastics (Documentation)

 

表一 部分塑料表面张力*（dyn/cm， 25℃）Table 1 Surface tension of plastics

塑   料 Plastic	表 面 张 力 Surface tension	塑   料 Plastic	表 面 张 力 Surface tension
PTFE 聚四氟乙烯	18.5	PVC	39.0
PVF 聚偏二氟乙烯	28.0	PMMA	39.0
PCTFE 聚三氟氯乙烯	31.0	PVDC	40.0
PE	31.0	PET	44.0
PS	33.0	PP	29

 

所以PTFE塑料是表面张力很低的一种塑料。

So PTFE is a plastic with very low surface tension.

三、常见液体的表面张力（文献记录）Surface Tension of Common Liquids (Documentation)

表2.几种典型液体的表面张力*(dyn/cm，25℃) Table 2. Surface tension of several typical liquids

液体            Liquid	表面张力 Surface tension	液体  Liquid	表面张力   Surface tension
水 Water	72.88	甲醇  methyl alcohol	22.6
蓖麻油（植物油） caster oil	36	乙二醇乙醚 ethylene glycol	30
苯 benzene	29	碳酸丙烯酯 propylene carbonate	30
乙醇      ethyl alcohol	24	六氟磷酸锂 Lithium hexafluorophosphate	36
丙酮          acetone	24	甲酰胺 formamide	59.13
双氧水 hydrogen peroxide	78.97	次氯酸 hypochlorous acid	29.6
IPA（异丙醇）	22	\	\

 

 

 

 

 

 

 

 

四、疏油的测试方法（《AATCC118-2002拒油性：碳氢化合物的阻抗测试》）

Test method for Oil Repellency (AATCC118-2002 Oil Repellency: Impedance Test of Hydrocarbons)

1.疏油性测试是由美国纺织化学师与印染师协会（AATCC）118-1989标准测试的。The oleophobic test was performed by the American Association of Textile Chemists and Printmakers (AATCC) Standard 118-1989.

1.1测试方法是：将已知表面张力的液体滴在材料的表面，观察润湿情况，吸附以及接触角度的情况，评出材料的拒油性能，拒油级别是以不润湿的测试试液为最高的编号。The test method is to drop a liquid with known surface tension on the surface of the material, observe the wetting condition, adsorption and contact Angle, and evaluate the oil repellent property of the material. The oil repellent grade is the highest number of the non-wetting test liquid.

2.测试设备及试剂 Test devices and reagents

2.1 拒油等级标准试液，按照下表准备。Prepare the reagents according to the table as below.

2.2 滴瓶：通常采用容量为了30ml的滴瓶，瓶外贴上液体名称的标签纸。Drop bottle is usually use 30ml with a label of the name of the reagents on the outside

2.3 橡胶吸头 Rubber suction

2.4 白色AATCC吸水纸 White AATCC absorbent paper

2.5 试验手套 Gloves

2.6 标准试液 Standard test reagents

3.测试样品 Test Sample

3.1 二块样品尺寸为20cm*20cm Two specimen size 20x20cm

3.2 试样测试前，放在标准大气下调湿至少4小时。Samples are placed in standard atmosphere for at least 4 hours before testing

3.3 测试程序 Test procedure

3.3.1 将试样平放在光滑的平面上，试样下面垫上白色吸水纸。当试样比较稀薄时，需用两层面料，避免测试液润湿底表面，以确保级数不受下层润湿衬纸的影响。Place the sample flat on a smooth surface and pad white absorbent paper underneath the sample. If the sample is relatively thin, two layers of sample should be used to avoid wetting the bottom surface with the test solution, so as to ensure that the grade is not affected by the wetting of the bottom lining paper.

3.3.2沿着测试样品纬纱方向5个位置从最低等级的测试液1级开始滴油（油滴的直径大约为5mm或体积为0.05ml,油滴之间至少相距4.0cm），滴油时，油滴距面料约0.6cm. Drop the reagent from the lowest grade of  1 at 5 locations along the weft direction of the test sample (the diameter of the oil drops is approximately 5mm or the volume is 0.05ml, and the reagent drops are at least 4.0cm apart). Drop the reagent about 0.6cm away from the sample

3.3.3从约45°角的方向观察液滴30±2s时间内的润湿情况，如果没有出现润湿现象，再滴一滴高一号的试液。Observe the wetting condition of the droplet within 30±2s from an Angle of about 45°. If there is no wetting phenomenon, drop a drop of higher rate test reagent.

3.3.4 重复以上操作，直到试样在30±2s时间内在液滴下面或液滴周围出现明显的润湿为止，织物润湿的正常迹象是油滴周围织物变深，油滴消失，油滴处圆外圆渗化或油滴闪光消失。Repeat the above procedure until obvious wetting appears under or around the droplet within 30±2s. Normal signs of sample wetting are darkening of the sample around the droplet, disappearance of the droplet, exocurination of the droplet, or disappearance of the gleam of the droplet

3.4.5 滴油中若有3滴或者更多滴通过，则表示这个级别通过。反之，有3滴或者更多没通过则表示没有通过这个级别。If 3 or more drops of the drop pass, this level passes. Conversely, a failure of 3 or more drops indicates a failure

4.测试报告Test report

测试报告应包含以下内容：The test report should contain the following

4.1 如果2块样品的拒油等级级别相同，报告这个级数 If 2 samples have the same oil repellency grade, report this grade

4.2 如果2块样品的级别不同，再测试第三块样品，第三块样品的结果与前2块样品中农的任何一个相同是，报告与第三块样品的级数相同 If the grade of the two samples is different, the third sample will be tested again. If the result of the third sample is the same as that of any of the first two samples, the grade of the third sample is reported as the same
4.3 如果第三块样品的级数与前两块样品不同，报告中间级数，拒油数精确到0.5级 If the grade of the third sample is different from the first 2 samples, report the intermediate grade with the oil repellency number accurate to 0.5 grade

五、施柏德科技对PTFE透气膜材料进行疏油测试 PTFE waterproof and breathable membrane Oleophobic test by SST

1.准备7种测试液体（水，机油，甲酰胺，甲醇，双氧水，乙二醇乙醚，酒精），其名称和表面张力如下：Prepare 7 test liquids (water, oil, formamide, methanol, hydrogen peroxide, ethylene glycol ether, alcohol) with their names and surface tensions as follows:

NO.	Liquid	Surface tension dyn/cm
1#	水 Water	72.88
2#	蓖麻油（植物油）Oil	36
3#	甲酰胺 formamide	59.13
4#	甲醇 methanol	22.6
5#	双氧水 hydrogen peroxide	78.97
6#	乙二醇乙醚 ethylene glycol ether	30
7#	乙醇alcohol	24

 

 

2.选取两款防水透气膜（①BD06200300-ASY疏油②BD06200300 不疏油 ）长*宽=10*5CM大小；Choose two type of test sample （①BD06200300-ASY oleophobic ②BD06200300 non-oleophobic ）L*W=10*5CM

3.按照 《AATCC118-2002拒油性》测试程序 Follow the <AATCC118-2002 oil repellent>test procedure

• 1）将样品平放在光滑的平面上，试样下面垫上白色吸水纸；Place the sample on a smooth surface with white absorbent paper underneath the sample
• 2）沿着测试样品方向纵向位置从上置下开始滴试剂（试剂的直径大约为5mm，试剂之间至少相距0cm），滴试剂时，试剂距样品约0.6cm. Drop the reagent vertically along the direction of the test sample from above (the diameter of the reagent is about 5mm, and the reagent is at least 0cm apart). Drop the reagent about 0.6cm away from the sample.
• 3）从约45°角的方向观察液滴30±2s时间内的润湿情况，如果没有出现润湿现象，再滴另外一种试液。Observe the wetting of the droplet within 30±2s from an Angle of about 45°. If no wetting occurs, drop another test solution
• 4）重复以上操作，直到试样在30±2s时间内在液滴下面或液滴周围出现明显的润湿为止，样品润湿的正常迹象是样品周围颜色变深，试剂消失，试剂处圆外圆渗化或试剂闪光消失 Repeat the above procedure until the sample is visibly wet under or around the droplet within 30±2s. Normal signs of sample wetting are darkening of the color around the sample, disappearance of the reagent, exocircuation at the reagent, or disappearance of the reagent flash
• 5）试剂滴中若有3滴或者更多滴通过，则表示样品通过测试。反之，有3滴或者更多没通过则表示没有通过这个测试 If 3 or more drops of the reagent pass, the sample passes the test. Conversely, failing three drops or more means failing the test

4.测试结果 Test result

①从图可知未疏油产品BD06200300，试剂2#机油（36 dyn/cm），4#甲醇(22.6 dyn/cm)，7#乙醇(24 dyn/cm)，没有拒油能力，表面张力的液体越低，润湿效果越明显；It can be seen from the figure that the non-oleophobic product BD06200300, reagent 2# oil (36 dyn/cm), 4# methanol (22.6 dyn/cm), 7# ethanol (24 dyn/cm), no oil rejection ability, the lower the surface tension of the liquid, the more obvious the wetting effect;

②从图中可知，BD06200300-ASY对所有测试试剂都有疏油效果，但表面张力越低的液体，接触角θ越小，润湿张力越大，越可能润湿材料； It can be seen from the figure that BD06200300-ASY has an oleophobic effect on all test reagents, but the lower the surface tension of the liquid, the smaller the contact Angle θ, the larger the wetting tension, the more likely to wet the material.

③施柏德科技的产品BD06200300-ASY的疏油产品可拒试剂甲醇（22.6dyn/cm），达到了AATCC118标准的7级疏油效果。 The waterproof and air permeable membrane BD06200300-ASY of  can reject methanol (22.6dyn/cm), achieving the 7 oil repellent effect of AATCC118 standard.