Polyglycerine

About This Product

Polyglycerine, also called polyglycerol, is made by condensing glycerine on itself under alkaline catalysis and vacuum, joining the molecules through ether links into short chains. Commercial grades run from diglycerol to decaglycerol and are viscous, pale, water-soluble liquids or soft solids.

It is best understood as glycerine with the dial turned up. A single glycerol molecule carries three hydroxyl groups; a decaglycerol carries twelve, on a backbone roughly ten times the mass. That raises molecular weight, viscosity and boiling point while keeping, and in fact increasing, the water affinity, so higher grades are stronger humectants than glycerine but far less volatile and less prone to the sticky feel of glycerine at high dose. Above about tetraglycerol the HLB exceeds 15, which is what makes the material useful in its own right as a solubiliser and dispersing agent, able to replace ethoxylated solubilisers and pearlising agents in formulations that must avoid ethylene oxide chemistry. Most of the tonnage, though, is not used as such: it is the backbone that becomes polyglycerol esters of fatty acids, the E475 emulsifier family, and polyglycerol polyricinoleate. The grade matters more than the name, since the polymerisation degree sets everything else, and it has to be specified on the order.

It is used as a humectant and moisturiser in personal care, as a solubiliser and dispersing agent replacing ethoxylates, for viscosity and density adjustment, as a feedstock for polyglycerol ester emulsifiers, and as a polyol in polyurethanes and alkyd resins.

Bio Green Oleo supplies polyglycerine to specification on polymerisation degree, hydroxyl value, colour, water content and pH, in 250 kg drums. State the grade, since diglycerol and decaglycerol behave quite differently.