Hansen Solubility Parameters via IGC problems and possibilities

Transcription

1 Hansen Solubility Parameters via IGC problems and possibilities 4th Interna?onal IGC Symposium 2015 Basel 9 June 2015 Prof Steven Abbo- Steven Abbo- TCNF Ltd steven@stevenabbo-.co.uk Some slides are sta?c images of things shown live during my talk

2 Formulating for compatibility We need compa?bility in order: To dissolve a polymer in a solvent To combine two polymers To put a pharmaceu?cal into a polymer To disperse nanopar?cles in solvents and polymers How do we calculate compa?bility? Not by hydrophilic/hydrophobic too crude Not by polar/non- polar too crude Not by quantum mechanical calcula?ons too?me- consuming We know that like is compa?ble with like so how do we calculate like?

3 Answer: Hansen Solubility Parameters Every solvent, polymer, pharmaceu?cal, nanopar?cle can be described with 3 solubility parameters: δd = Dispersion, i.e. van der Waals corresponds to polarizability and to refrac?ve index δp = Polar, i.e. normal polarity corresponds to dipole moment δh = Hydrogen bonding Just as our intui?ons suggest Nothing complicated, obscure or surprising about them The parameters are pre-y intui?ve as we ll see live

4 HSPiP and a typical list of solvents

5 How do we calculate likeness from HSP? Calculate the HSP Distance (Ra) which is the simple distance in 3D If one en?ty is δd 1, δp 1, δh 1 and the other is δd 2, δp 2, δh 2 then Distance²= 4(δD 1 - δd 2 )²+(δP 1 - δp 2 )²+(δH 1 - δh 2 )² With the famous factor of four that privileges δd A large distance means incompa?ble, a small distance means compa?ble Works for solvents, polymers, cosme?cs, nanopar?cles, skin, food packaging barriers, organophotovoltaics, paints, So all we need are the HSP of our materials!

6 Carbon Nanotubes How do we get HSP values? For solvents it can be done via thermodynamic proper?es such as enthalpy of vapourisa?on, refrac?ve index, dipole moment etc. For solids (polymers, nanopar?cles) it can be done via the 20 solvent technique Put a small sample in each of ~20 tubes, put a different solvent in each tube and score 1 for happy and 0 for unhappy Then find the HSP value which means that all the good solvents are inside the HSP sphere and all the bad ones outside it That defines the HSP and the radius which defines how choosy the material is Let s see that live 1 ß Borderline à 0

7 HSP calculated via the Sphere

8 Why do we need IGC? The standard technique is very bad for liquids such as pharma/ cosme?c excipients They are too soluble in too many solvents If the interac?on of the IGC probes with a (semi- )liquid sta?onary phase depends on likeness then probes that are unlike will elute quickly and those that are like will elute slowly With correc?ons for vapour pressure, molar volume etc. So IGC could revolu?onise the measurement of HSP If we could get the right correla?on between reten?on and HSP!

9 How might IGC work for HSP? There s an app for that! Abbo- s Rule: No science without a formula No formula without an app I m doing the best I can in fields I know lots about via my Prac?cal X series Prac?cal Solubility Prac?cal Surfactants Prac?cal Adhesion Prac?cal Diffusion Prac?cal Chromatography (Under Construc?on) Let s go live! All free No adware, cookies or anything nasty Run on all devices, PC, Mac, Tablet, Phone Safe for corporate networks they are just HTML5/JavaScript/CSS3 With considerable help from Adscien?s and Inoly?x which I gratefully acknowledge

10 IGC Basics

11 Dispersive energy

12 Surface Morphology

13 Specific interactions

14 HSP via Χ parameters

15 Next steps? Please explore any of my Prac?cal X sites in areas that interest you Please feed back problems, issues, wish- lists I m always happy to fix things, extend apps, write new ones steven@stevenabbo-.co.uk In par?cular, what would help within Prac?cal Chromatography and in IGC specifically? e.g. should I upgrade the IGC apps to use reten?on?me instead of Vg? Over to your ques?ons (if the technology works!)