as I have to do the one-step bulk polymerization
for example if i have:
Polyethylene glycol (MW=6000g/mol)
Castor oil (MW=933g/mol)
Butanediol (MW=90g/mol)
Hexamethylene diisocyanate (MW=168.2g/mol)
Please specify the OH-number (or average OH-functionality) of your castor oil and the planned weigth or molar ratio of the polyol components (PEG and castor oil).
Castor oil (functionality of 2.67) with a hydroxyl number of 161.01 mg KOH/g and an acid number of 0.99 mg KOH/g
And weight ratio of PEG and castor oil will be 50/50.
1 mol PEG (6000 g) contains 2 hydroxyls, 1 g PEG contains 0.333 mmol hydroxyl. The equivalent weight of the castor oil is 56,000/161.01 (160.01 is the OH number) = 348, which means that 1 g castor oil contains 2.87 mmol hyldroxyl. Which means that 1 g of 50/50 wt% PEG 6000 and castor oil contains (0.333+2.87)/2= 3.203 mmol hydroxyl. You have to add diioscyanate in an amount which contains 3.203 mmol isocyanate (you can calculate it from the isocyanate equivalent) and you will get an isocyanate end-functionalized prepolymer with 3.203 mmol isocyanate groups. To this you have to add 3.203/2= 1.601 mmol butane diol. This calculation assumes that the addition of excess isocyanate prevents the reaction of bot ends of the isocyanate with the polyol and also assumes that there is no side reaction of the isocyanate. This, however, should be handled with care, it is a starting value which you have to try experimentally and find out from the testing of your products physical properties which is the optimum composition.
https://www.researchgate.net/post/How-to-calculate-the-molar-ratio-for-the-components-of-a-polyurethane-in-a-stoichiometric-value,kindly check this link.
http://wir-dauercamper.de/mole-ratio-calculator.html,u can follow this link.
https://www.researchgate.net/post/How-to-calculate-the-molar-ratio-for-the-components-of-a-polyurethane-in-a-stoichiometric-value,this link may be useful.
http://wir-dauercamper.de/mole-ratio-calculator.html,this link may be helpful.
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