Related Information About Solvent
Benzyl Alcohol is often the primary solvent and sometime the only solvent in a given formula. Its primary function is as a sterilizing agent. However, due to its solvency power it is often used to keep hormones in solution with oil or other vehicles. It is also one of the thinnest (that is best for viscosity reduction) The major drawback to this solvent is that it tends to make for painful injections if the concentration goes above 10%. (This is true for any low molecular weight alcohol). Less than this tends to be painless for most people.
Technical info: CAS # 100-51-6, Density is 1.05, Molecular weight is 108.14, Boiling point is 401f, Water solubility is 4.29g in 100ml.
Benzyl Benzoate is the next common solvent on the list. It is not nearly as strong and much heavier than the benzyl alcohol so benzyl benzoate is used primarily for its latent affects in the depot. Namely it helps keep the hormone in solution at the injection site after the more water-soluble benzyl alcohol has leached from the depot. benzyl benzoate is constructed of two benzene rings bridged by a carbonyl group, this making the solvent extremely hydrophobic. It is also painless at low levels and nearly painless at 15-20% for most people.
Technical info: CAS# 120-51-4, density is 1.11, Molecular Weight is 212.25 Boiling point is 614f, Water solubility is less then 1g in 100ml.
Propylene glycol is made ether from glycerol reacted with NaOH or from propylene reacted with chlorine and s carbonate. Hence it’s not very toxic. This shit is used for everything. It is one of the lightest polyhydric alcohols. Fairly polar solvent than can dissolve most any powder. Used as a co solvent for just about anything. Drawbacks include discomfort injecting at high levels and poor viscosity for the MW. Not the most compatable with oil.
Technical info: CAS# 57-55-6, Miscible in water. Specific Gravity:1.0361 boiling point 370f Molecular Weight is 76.1
Polyethylene glycol (PEG) is a polymer made for ethylene oxide. It comes in almost any MW, from 200 to 60,000. 400 to 12,000 are the most common with 400 the most common for liquids and 2,500 for solid. (Anything over 800 to 1,000 is a solid at room temp.) It is nontoxic at any reasonable level. It is nonpolar while having lots of hydroxyl functionality. This makes it great for getting things to stay soluble in oil. Used a lot for compatibility reasons. Can also be used as a painless vehicle, instead of oil. Drawbacks include high viscosity and thermoplastic tendencies becoming more pronounced at the higher MWs. Also has mechanical properties (surface tension) that cause it to separate from oil. This may become less pronounced at the higher MWs but I have not had a chance to test this at this time.
Technical info: CAS# 25322-68-3, Miscible in water at the lower MWs slowly decreasing as the MW goes up. Density: range: 1.1 to 1.2 (increases as molecular weight increases) Melting Point: Melting point increases as molecular weight increases: PEG 400 = 4-8C (39-46F) PEG 600 = 20-25C (68-77F) PEG1500 = 44-48C (111-118F)
Glycerol is glycerin and via versa. The first is a lab term and the second an industrial term. It is the binding component of fat, which is fat is one molecule of glycerol and 3 fatty acid chains. It is not a great solvent for the home brewer for a couple of reason. First and foremost do not inject glycerol undiluted. It is a strong dehydrogenating agent and can cause ruptures in cells. (OUCH) Oral it can even be taken as a diuretic. The second is that it is a very viscous solvent. It’s hard to thin. Can be used as a vehicle instead of oil.
Technical info: CAS# 56-81-5, Specific Gravity is 1.26, boiling point is 554f, Miscible in water, and has a Molecular Weight of 92.1