Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS Microgels
The phase transition behavior of differently crosslinked poly(<i>N</i>-isopropylacrylamide)/<i>N</i>,<i>N</i>’-methylenebisacrylamide (PNiPAM/BIS) microgels with varying crosslinker content is investigated in presence of aromatic additives. The influence of <i&...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-09-01
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| Series: | Gels |
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| Online Access: | https://www.mdpi.com/2310-2861/8/9/571 |
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| author | Daniel Schlattmann Monika Schönhoff |
| author_facet | Daniel Schlattmann Monika Schönhoff |
| author_sort | Daniel Schlattmann |
| collection | DOAJ |
| description | The phase transition behavior of differently crosslinked poly(<i>N</i>-isopropylacrylamide)/<i>N</i>,<i>N</i>’-methylenebisacrylamide (PNiPAM/BIS) microgels with varying crosslinker content is investigated in presence of aromatic additives. The influence of <i>meta</i>-hydroxybenzaldehyde (<i>m</i>-HBA) and 2,4-dihydroxybenzaldehyde (2,4-DHBA), chosen as model drugs, on the volume phase transition temperature (VPTT) is analyzed by dynamic light scattering (DLS), differential scanning calorimetry (DSC), and <sup>1</sup>H-NMR, monitoring and comparing the structural, calorimetric, and dynamic phase transition, respectively. Generally, the VPTT is found to increase with crosslinker content, accompanied by a drastic decrease of transition enthalpy. The presence of an additive generally decreases the VPTT, but with distinct differences concerning the crosslinker content. While the structural transition is most affected at lowest crosslinker content, the calorimetric and dynamic transitions are most affected for an intermediate crosslinker content. Additive uptake of the collapsed gel is largest for low crosslinked microgels and in case of large additive-induced temperature shifts. Furthermore, as temperature is successively raised, <sup>1</sup>H NMR data, aided by spin relaxation rates, reveal an interesting uptake behavior, as the microgels act in a sponge-like fashion including a large initial uptake and a squeeze-out phase above VPTT. |
| first_indexed | 2024-03-09T23:57:51Z |
| format | Article |
| id | doaj.art-da16508da6dd46069571c817d2e79a33 |
| institution | Directory Open Access Journal |
| issn | 2310-2861 |
| language | English |
| last_indexed | 2024-03-09T23:57:51Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Gels |
| spelling | doaj.art-da16508da6dd46069571c817d2e79a332023-11-23T16:22:18ZengMDPI AGGels2310-28612022-09-018957110.3390/gels8090571Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS MicrogelsDaniel Schlattmann0Monika Schönhoff1Institute of Physical Chemistry, University of Münster, Corrensstr. 28-30, 48149 Münster, GermanyInstitute of Physical Chemistry, University of Münster, Corrensstr. 28-30, 48149 Münster, GermanyThe phase transition behavior of differently crosslinked poly(<i>N</i>-isopropylacrylamide)/<i>N</i>,<i>N</i>’-methylenebisacrylamide (PNiPAM/BIS) microgels with varying crosslinker content is investigated in presence of aromatic additives. The influence of <i>meta</i>-hydroxybenzaldehyde (<i>m</i>-HBA) and 2,4-dihydroxybenzaldehyde (2,4-DHBA), chosen as model drugs, on the volume phase transition temperature (VPTT) is analyzed by dynamic light scattering (DLS), differential scanning calorimetry (DSC), and <sup>1</sup>H-NMR, monitoring and comparing the structural, calorimetric, and dynamic phase transition, respectively. Generally, the VPTT is found to increase with crosslinker content, accompanied by a drastic decrease of transition enthalpy. The presence of an additive generally decreases the VPTT, but with distinct differences concerning the crosslinker content. While the structural transition is most affected at lowest crosslinker content, the calorimetric and dynamic transitions are most affected for an intermediate crosslinker content. Additive uptake of the collapsed gel is largest for low crosslinked microgels and in case of large additive-induced temperature shifts. Furthermore, as temperature is successively raised, <sup>1</sup>H NMR data, aided by spin relaxation rates, reveal an interesting uptake behavior, as the microgels act in a sponge-like fashion including a large initial uptake and a squeeze-out phase above VPTT.https://www.mdpi.com/2310-2861/8/9/571poly(<i>N</i>-isopropylacrylamide)VPTTcrosslinkerthermoresponsivemicrogeladditive |
| spellingShingle | Daniel Schlattmann Monika Schönhoff Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS Microgels Gels poly(<i>N</i>-isopropylacrylamide) VPTT crosslinker thermoresponsive microgel additive |
| title | Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS Microgels |
| title_full | Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS Microgels |
| title_fullStr | Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS Microgels |
| title_full_unstemmed | Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS Microgels |
| title_short | Interplay of the Influence of Crosslinker Content and Model Drugs on the Phase Transition of Thermoresponsive PNiPAM-BIS Microgels |
| title_sort | interplay of the influence of crosslinker content and model drugs on the phase transition of thermoresponsive pnipam bis microgels |
| topic | poly(<i>N</i>-isopropylacrylamide) VPTT crosslinker thermoresponsive microgel additive |
| url | https://www.mdpi.com/2310-2861/8/9/571 |
| work_keys_str_mv | AT danielschlattmann interplayoftheinfluenceofcrosslinkercontentandmodeldrugsonthephasetransitionofthermoresponsivepnipambismicrogels AT monikaschonhoff interplayoftheinfluenceofcrosslinkercontentandmodeldrugsonthephasetransitionofthermoresponsivepnipambismicrogels |