包礼SCformulations水悬浮剂

1、SC formulations Suspension Concentrates论坛（第十届山东省农药信息交流会）1SC 水悬浮剂描述：固体颗粒悬浮于水中 Description: Solid particles suspended in water 常见问题Issues悬浮物质与水之间存在密度差 Density difference between suspended matter and water如果原药密度大于1克/毫升将形成沉淀 Will form sediment if density is 1如果原药密度大于1克/毫升将漂浮 Will float if density is Ca.

2、i. large大粒径4How to prevent Oswald ripening怎样预防奥氏熟化的发生较窄的粒径分布范围 Narrow particle size distribution还有其他的诀窍 There are other tricks: Very limited amount of diluted oil in aqueous phase 将一定量的油稀释到水相中 5To make an SC 水悬浮剂制备Preparation of small particles 小粒子的制备Preventing flocculationPreventing sedimentation6T

3、o make an SC 水悬浮剂制备Preparation of small particles 小粒子的制备Small suspended particles are prepared by milling process 通过砂磨设备获得较小粒径Processing conditions are important 生产工艺条件很重要7To make an SC 水悬浮剂制备Preparation of small particles 小粒子的制备8Milling砂磨Wetting - Dispersion - stabilization润湿 分散 稳定性9Issue during mi

4、lling process砂磨过程中出现的问题During milling process fresh surface is generated砂磨过程中新的粒子表面产生Fresh surface is generally of non-polar nature en will cluster together rapidly新产生的非极性的表面通常是的自然对开很容易迅速聚集This could lead to increased viscosity and even mill blockage这可能导致粘度增加甚至阻碍砂磨进程To overcome mill blockage a wetti

5、ng agent is needed为了克服这一问题所以润湿剂的加入是非常必要的10To make an SC 水悬浮剂制备Preparation of small particlesPreventing flocculation 絮凝的预防Preventing sedimentation11How to prevent flocculation? 怎样预防絮凝的产生Use of dispersants 分散剂的使用Dispersant should be firmly locked on substrateAnchoring 锚固作用Dispersant types: 分散剂种类Anioni

6、c阴离子 Electrostatic stabilisation静电稳定作用CaDDBS / NaDDBS（十二烷基苯磺酸钙/钠）Fosfate esters （磷酸酯类）Non ionic非离子 Steric stabilisation 空间位阻稳定作用Alcohol etoxylates（乙氧基醇醚类）Polymeric dispersants（高分子表面活性剂）Mix of the two Electrosteric stabilisation混合静电/空间位阻Naphtalene condensate sulfonates (萘磺酸盐甲醛缩合物)Lignin sulfonates （木

7、质素磺酸盐类）12Electrostatic Stabilization静电排斥作用GhGmaxElectrostatic静电学Electrosteric静电空间GhGh 132dM h G h d2dp Monomer单体-Polymer高分子Steric Stabilization空间位阻作用空间位阻是由于非离子表里面活性剂和/或高分子表面活性剂提供的Steric barriers are produced by adsorption of nonionic surfactants and/or polymeric surfactant由于链的不利交叉排斥和熵值作用对重大交叠的影响Repu

8、lsion is due to unfavourable mixing of the chains and entropic effects on significant overlap14Functions of surfactants表面活性剂的功能Wet 润湿Disperse 分散15Functions of surfactants表面活性剂的功能Wet 润湿作用Dynamic molecules to wet surface during milling stage在砂磨期间动态分子润湿新鲜的表面Smaller molecules 分子量较小Negative regarding sta

9、bility 对稳定性有负面影响Disperse 分散作用Larger molecules to stabilise suspended particles大分子对粒子提供稳定的悬浮支撑作用Act slow 作用进程缓慢16Size does matter 分子大小关系Dispersed Phase 分散内相CONVENTIONAL DISPERSANT 常规分散剂POLYMERIC DISPERSANT 高分子分散剂Dispersed Phase 分散内相172dM h G h d2dp Monomer单体-Polymer高分子Steric Stabilization空间位阻作用空间位阻是由

10、于非离子表里面活性剂和/或高分子表面活性剂提供的Steric barriers are produced by adsorption of nonionic surfactants and/or polymeric surfactant由于链的不利混合排斥和熵值作用对重大交叠的影响Repulsion is due to unfavourable mixing of the chains and entropic effects on significant overlap18Rheology pro agent vs. polymeric dispersant 润湿剂与高分子分散剂流变性特征对

11、比Wetting agent 润湿剂 Polymeric dispersant高分子分散剂 No shear effect polymeric dispersant flow curve: suspension is properly stabilized高分子分散剂在剪切作用下的流变曲线无影响：悬浮液相对稳定 Wetting agent flow curve increases hugely at low shear: insufficient stabilisation润湿剂在低剪切作用下的流变曲线明显增大：不够稳定 If wetting agent is required, use at

12、 low possible concentration!如果润湿剂是必须添加的，尽可能在最低添加量下使用19To make an SC 水悬浮剂制备Preparation of oil droplets in waterPreventing coalescencePreventing sedimentation 沉淀的预防20Stokes law 斯托克斯定律 Vs = velocity of settling /creaming粒子沉降速度，cm/s; = viscosity 水悬浮剂粘度，Pa.S;g = gravity 重力加速度， cm/s;r = radius of sphere 分

13、散介质粒子直径，cm; = density difference sphere & continuous phase 分散粒子的密度与水的密度差Vs=-92gr221Stokes law 斯托克斯定律 Vs=-92gr2No sedimentation if density of suspended matter and water phase are equal如果悬浮介质和水相之间没有密度差，沉淀问题就不可能发生固相/液相密度差=022Stokes law 斯托克斯定律 Vs=-92gr2The smaller the particle size, the lesser sedimenta

14、tion粒径越小沉淀越慢Note this a square function值得注意的是称将速度与粒径的平方正相关10 times the particle size is 100 times faster sedimentation10倍的粒径大小差异将导致100倍的沉降速度差别粒径大小23Stokes law 斯托克斯定律 Vs=-92gr2Increased viscosity will reduce sedimentation提高粘度有利于减少沉降However viscosity cannot be increased infinitely然而粘度不可能被无限制的增加Need of

15、 shear thinning rheology modifier需要使界面内剪切力变小的流体改性物Xanthan or Kelzan Gum provides this effect黄原胶可以提供这种作用体系粘度24Rheology pro gum黄原胶的流变学特征粘度转速25SC 水悬浮剂General formula:一般配方组成 成份 用量Suspended phase分散相40%Dispersant分散剂4%Wetting agent润湿剂 0.5%Glycerine 防冻剂5.2%Anti foam 消泡剂0.1%Preservative防腐剂 0.1%Kelzan gum增稠剂

16、0.1%Water水50%Issue: long term stability and emulsion stability upon dilution 问题：经时稳定性和乳液的稀释稳定性26Croda SC recommendation英国禾大公司在水悬浮剂方面的核心产品Dispersants:分散剂Atlox 4913 羧酸盐枝接物Atlox Metasperse 100L 羧酸盐修饰物Atlox Metasperse 500L 羧酸盐修饰物Co dispersant/wetting agent:助分散剂/润湿剂Atlas G-5000 高分子嵌段共聚物Atlas G-5002L 高分子前

17、段共聚物Atlox 4894 高分子前段共聚物Traditional wetting agent: 传统润湿剂Synperonic A7 聚氧乙烯醇醚27Further guidelines 使用说明Dispersant level 10% of dispersed phase 分散剂的用量通常是分散内相的10%30 % dispersed phase 30%的分散内向3% total surfactants 需要3%的总的分散剂Ratio dispersant/co-dispersant: 2:1分散剂和助分散剂的比例为2：12% Atlox 4913 分散剂1% Atlox 4894 助分

18、散剂With traditional wetting agent: 配以传统的润湿剂2% Atlox 4913 分散剂1% Atlas G-5002L 助分散剂Minimum amount Synperonic A7 最小量的润湿剂28With traditional wetting agent传统的润湿剂用量的确定Optimum approach:最理想的途径三元复配组合12 34 5 67 8 9 1011 12 13 14 1516 17 18 19 20 2122 23 24 25 26 27 2829 30 31 32 33 34 35 36 3738 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 5657 58 59 60 61 62 63 64 65 66 67Dispersant 分散剂Co-dispersant 助分散剂Wetting agent 润湿剂Performance criteria:评估标准Milling efficiency 砂磨的效率Storage stability 储存稳定性29Crystal growth; part II结晶增长PolymericDispersant高分子分散剂Polymeric plus monomeric Dispersant高分子/单体分散剂30Crystal