Polawax, polysorbate 20, PEG-40 hydrogenated castor oil or Caprol Micro Express as the main ingredient isn't the best idea. Why? We use positively charged or cationic ingredients in a conditioner as the emulsifier so it will adsorb or form a film on our hair. This process is called substantivity. (Click here for a longer description on how conditioners work!) These ingredients are non-ionic or neutrally charged, and anything you make using them will be more like a lotion than a conditioner. This means you might get some moisturization from the emollients, but you won't get any conditioning.
Instead, you'll want to use cationic emulsifiers like like Incroquat BTMS-50, Rita BTMS-225, Incroquat CR, or cetrimonium bromide as your main ingredient in a conditioner. You can add loads of non-ionic or neutrally charged ingredients into the conditioner - things like panthenol or aloe vera or glycerin and so on - but you want the main emulsifier to positively charged.
lower the pH of a conditioner when you've made it. Conditioners made with the positively charged ingredients I mention above will be a pH 6 or lower.
Can you substitute BTMS-25 for BTMS-50? Yes, most of the time. Check out this post for more information!
Hair care section of the blog
Conditioner: What's that then?
Conditioner: Defining our conditioners
Conditioner: The basic recipes
What's important in a conditioner? Part one
What's important in a conditioner? Part two
Back to the very basics: Conditioner
Leave-in conditioner with kera straightening and lycopene
Coconut oil and pisum satvum rinse off conditioner