How does the sonication process affect the molecular structure of PAN in DMF, leading to an increase in viscosity?
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The sonication process affects the molecular structure of polyacrylonitrile (PAN) in N,N-dimethylformamide (DMF) by influencing the dipole-dipole interactions between polar nitrile groups. Sonication treatment can reduce the relative average molecular weight of PAN, leading to a broader molecular weight distribution. Additionally, sonication treatment can improve the electrospinnability of high-viscosity PAN solutions by enhancing rheological properties, increasing electric conductivity, and reducing surface tension. This alteration in molecular structure due to sonication results in improved solution properties, ultimately leading to an increase in viscosity of the PAN solution in DMF.
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| Papers (5) | Insight |
|---|---|
| Sonication with SDS in DMF increases PAN's crystalline structure, lowering cyclization initiation temperature by 8.5°C, enhancing viscosity due to improved molecular interactions. | |
17 Citations | Sonication treatment in PAN/DMF solution increases solution viscosity by disentangling molecular chains, exposing more polar groups, and enhancing electric conductivity, ultimately improving electrospinnability. |
11 Citations | Sonication in DMF doesn't directly impact PAN's molecular structure in the study. Instead, the viscosity increase is influenced by dipole-dipole interactions between nitrile groups affecting MWD-dependent behavior. |
| Ultrasonic treatment in PAN dissolution reduces molecular weight, broadens distribution, and accelerates dissolution by transforming the swelling method, impacting viscosity in DMF. | |
Open access•Journal Article 1 Citations | Not addressed in the paper. |
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