Polymer chemistry
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keerthanapadma
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Polymer chemistry
Can someone help me out in finding the preparation method of sodium polyacrylate, SAP? I found it is acrylic acid, NaOH, sodium persulftae as initiator. Can someone say me about the composition or amount of each substance need to be added?
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norman40
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Re: Polymer chemistry
Hi keerthanapadma,
My suggestion is that you try an online search with terms like “preparation of sodium polyacrylate” or “synthesis of sodium polyacrylate”. Google Scholar is a good option for searching technical information.
I hope this helps. Please post again if you have more questions.
A. Norman
My suggestion is that you try an online search with terms like “preparation of sodium polyacrylate” or “synthesis of sodium polyacrylate”. Google Scholar is a good option for searching technical information.
I hope this helps. Please post again if you have more questions.
A. Norman
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keerthanapadma
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- Joined: Tue Sep 24, 2019 5:11 am
- Occupation: Student
Calculating amount of sodium acrylate salt formed
Hi everyone. My question may look so simple but I wish to clear my doubt on some basics. I am preparing a reaction for producing polymer, sodium polyacrylate. For this,
1) 1M Acrylic acid CH2CHCOOH solution is prepared of 300 mL.
2) 1M NaOH solution is prepared of 300 mL.
3) Both were mixed to obtain pH=7. The reaction is as follows:
CH2CHCOOH + NaOH = CH2CHCOO-Na+. This may not be actual reaction, since dissociation of weak acid also matters.
Here, it is weak acid and strong base mixed at neutral pH. The acid will be in both dissociated and undissociated form. Now How do I calculate the sodium acrylate salt formed?
Though it looks simple, I am not satisfied in its calculation. Kindly do help.
1) 1M Acrylic acid CH2CHCOOH solution is prepared of 300 mL.
2) 1M NaOH solution is prepared of 300 mL.
3) Both were mixed to obtain pH=7. The reaction is as follows:
CH2CHCOOH + NaOH = CH2CHCOO-Na+. This may not be actual reaction, since dissociation of weak acid also matters.
Here, it is weak acid and strong base mixed at neutral pH. The acid will be in both dissociated and undissociated form. Now How do I calculate the sodium acrylate salt formed?
Though it looks simple, I am not satisfied in its calculation. Kindly do help.
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MadelineB
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Re: Polymer chemistry
Hello Keerthanapadma,
I've merged your most recent post with the thread from your other posts on this topic. Please keep your posts in the same thread so the expert who was helping you can see that you have follow-up questions.
Thank you,
Madeline
Moderator
I've merged your most recent post with the thread from your other posts on this topic. Please keep your posts in the same thread so the expert who was helping you can see that you have follow-up questions.
Thank you,
Madeline
Moderator
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norman40
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Re: Polymer chemistry
Hi keerthanapadma,
You are correct that acrylic acid is a weak acid and that it is partially dissociated in water. But it will react with a strong base (NaOH) to form the acrylate anion. Combining the same molar amounts of NaOH and acrylic acid as you described will provide equimolar amounts of Na and acrylate ions in solution. Please note that the final solution would be expected to have a pH greater than 7 due to the presence of the acrylate ions.
Some additional information about acid/base equilibria and associated calculations is available in the following links:
https://chem.libretexts.org/Bookshelves ... trong_Base
https://www.chemguide.co.uk/physical/ac ... acids.html
I hope this helps. Please post again if you have more questions.
A. Norman
You are correct that acrylic acid is a weak acid and that it is partially dissociated in water. But it will react with a strong base (NaOH) to form the acrylate anion. Combining the same molar amounts of NaOH and acrylic acid as you described will provide equimolar amounts of Na and acrylate ions in solution. Please note that the final solution would be expected to have a pH greater than 7 due to the presence of the acrylate ions.
Some additional information about acid/base equilibria and associated calculations is available in the following links:
https://chem.libretexts.org/Bookshelves ... trong_Base
https://www.chemguide.co.uk/physical/ac ... acids.html
I hope this helps. Please post again if you have more questions.
A. Norman