Home Cosmetic Science Talk Formulating help working with thickeners, salt and HEC

  • help working with thickeners, salt and HEC

    Posted by domicanica on February 19, 2021 at 2:37 am

    hi. as the title states, i’m having a hard time thickening my body wash. i’ve tried salt and HEC so far. i know that the formula must have an anionic surfactant to thicken with salt but i’m not seeing results when i use it with SCI. for instance..

    these worked fine:
    water 65.5%
    sodium methyl cocoyl taurate 10%
    sodium cocoamphoacetate 9%
    decyl glucoside 8%
    lauryl glucoside 5%
    sodium chloride 2.5%

    water 60%
    sodium methyl cocoyl taurate 8%
    sodium cocoamphoacetate 15%
    decyl glucoside 10%
    glycerin 5%
    sodium chloride 2%

    these failed, they stayed liquid:
    water 67%
    sci 10%
    sodium cocoamphoacetate 10%
    decyl glucoside 10%
    urea 5%
    sodium chloride 2%

    water 67%
    sci 10%
    sodium cocoamphoacetate 10%
    decyl glucoside 10%
    glyceryl oleate 1%
    sodium chloride 2%

    there was virtually no thickening. my sci is in powder form. i added the sci to the liquid surfactants and did a water bath to heat it up so it would be easier to mix. once the surfactants turned into a paste i added water then the urea/glyceryl oleate, then the salt. was i supposed to wait for the mixture to cool down fully before adding salt? i doubt it, because i did the exact same process in the 2 formulas that did work so what’s the issue now, is it just the SCI? did i just need more salt?

    i also noticed that when i use HEC as a thickener it takes on a hair-gel-in-water texture.

    i tried:
    water 52%
    lauryl glucoside 20%
    cocamidopropyl betaine 18%
    caprylyl/capryl glucoside 4%
    glycerin 5%
    HEC 1%

    water 71%
    cocamidopropyl betaine 6%
    caprylyl/capryl glucoside 12%
    glycerin 8%
    HEC 2%
    eucalyputus eo 1%

    both turned into gel then separated into gel and water. what am i doing wrong? does HEC work at a specific ph or anything?

    grateful for any comments/feedback.

    markbroussard replied 3 years ago 3 Members · 3 Replies
  • 3 Replies
  • chemicalmatt

    Member
    February 19, 2021 at 8:07 pm

    @domicanica there’s too much to go into here. You need to read up on surfactant chemistry a bit more. Some basic advice: salt does not thicken all surfactant systems, and has little to no effect on those with APG glucosides. As for HEC, that will usually gel out in these systems, especially with all of those $#!#! glucosides. You need to use hydroxymethylcellulose or just methylcellulose. You’ll feel better then.

  • domicanica

    Member
    February 19, 2021 at 8:50 pm

    Thanks @chemicalmatt , I’m aware that salt only really works when there’s an anionic present and doesn’t thicken non-ionics well. I just don’t understand why it would work with one anionic and not the other. I have hydroxymethylcellulose on hand, I’ll just see what happens with that. Any recommended reading for surfactant chemistry?

  • markbroussard

    Member
    February 20, 2021 at 3:05 am

    @domicanica

    I just tried for the first time Sorbithix L100 from Applechem (Sorbeth-230 Tetraoleate (and) Decyl Glucoside (and) Sorbitan Laurate - also available in small quantities from MakingCosmetics) in a system comprised of CAPB, Coco-Glucoside, Lauryl-Glucoside … works like a charm, simple drop-in yielding nice viscosity and good clarity.

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