Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating
Rigid polyurethane foam (RPUF) has been widely used in many fields, but its high flammability and frequent release of large amounts of toxic smoke during combustion limit its application. Hydrogel coatings, as a kind of environmentally friendly material, contain large amounts of water, which is bene...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/23/20/12632 |
| _version_ | 1797440833954250752 |
|---|---|
| author | Bin Chen Lizhong Yang |
| author_facet | Bin Chen Lizhong Yang |
| author_sort | Bin Chen |
| collection | DOAJ |
| description | Rigid polyurethane foam (RPUF) has been widely used in many fields, but its high flammability and frequent release of large amounts of toxic smoke during combustion limit its application. Hydrogel coatings, as a kind of environmentally friendly material, contain large amounts of water, which is beneficial to flame retardance of RPUF. MXene, as a two-dimensional inorganic nanomaterial, possesses a large specific surface area and good thermal stability, performing well in smoke suppression and as a physical barrier for flammable gas products and heat. Herein, to address the fire hazards of RPUF, MXene nanosheets were first grafted with double bonds, and then introduced into a polyacrylamide hydrogel system by radical polymerization to prepare MXene-based hydrogel coating (PAAm-MXene). The flame-retardant RPUF (coated RPUF) was prepared by painting the PAAm-MXene coating onto RPUF surface. The dispersion of modified MXene nanosheets (m-MXene) in hydrogels is improved compared with pristine MXene, and the addition of m-MXene contributes to the thermal stability enhancement of PAAm-MXene. Cone calorimetry, water retention test, and open flame combustion test were used to study the flame retardancy, smoke suppression, and water retention of flame-retardant RPUF. The coated RPUF exhibited significant flame retardancy, including reduced peak heat release rate (pHRR) at a maximum by 25.8%, and total heat release rate (THR) at a maximum by 24.6%, and total smoke production at a maximum by 38.9%. The results show that both MXene and m-MXene can improve the flame retardancy, smoke suppression, and water retention of hydrogels, but m-MXene has a better smoke suppression effect than MXene. That can be ascribed to the better dispersion of m-MXene than pristine MXene. The detailed performance improvement mechanisms are proposed. This work will not only improve the flame retardancy of RPUF, but also promotes the exploration of new flame-retardant strategies for RPUF. |
| first_indexed | 2024-03-09T12:15:08Z |
| format | Article |
| id | doaj.art-b05a63065a7f4dffa92112415c356538 |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-09T12:15:08Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-b05a63065a7f4dffa92112415c3565382023-11-30T22:48:06ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672022-10-0123201263210.3390/ijms232012632Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite CoatingBin Chen0Lizhong Yang1State Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei 230026, ChinaState Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei 230026, ChinaRigid polyurethane foam (RPUF) has been widely used in many fields, but its high flammability and frequent release of large amounts of toxic smoke during combustion limit its application. Hydrogel coatings, as a kind of environmentally friendly material, contain large amounts of water, which is beneficial to flame retardance of RPUF. MXene, as a two-dimensional inorganic nanomaterial, possesses a large specific surface area and good thermal stability, performing well in smoke suppression and as a physical barrier for flammable gas products and heat. Herein, to address the fire hazards of RPUF, MXene nanosheets were first grafted with double bonds, and then introduced into a polyacrylamide hydrogel system by radical polymerization to prepare MXene-based hydrogel coating (PAAm-MXene). The flame-retardant RPUF (coated RPUF) was prepared by painting the PAAm-MXene coating onto RPUF surface. The dispersion of modified MXene nanosheets (m-MXene) in hydrogels is improved compared with pristine MXene, and the addition of m-MXene contributes to the thermal stability enhancement of PAAm-MXene. Cone calorimetry, water retention test, and open flame combustion test were used to study the flame retardancy, smoke suppression, and water retention of flame-retardant RPUF. The coated RPUF exhibited significant flame retardancy, including reduced peak heat release rate (pHRR) at a maximum by 25.8%, and total heat release rate (THR) at a maximum by 24.6%, and total smoke production at a maximum by 38.9%. The results show that both MXene and m-MXene can improve the flame retardancy, smoke suppression, and water retention of hydrogels, but m-MXene has a better smoke suppression effect than MXene. That can be ascribed to the better dispersion of m-MXene than pristine MXene. The detailed performance improvement mechanisms are proposed. This work will not only improve the flame retardancy of RPUF, but also promotes the exploration of new flame-retardant strategies for RPUF.https://www.mdpi.com/1422-0067/23/20/12632rigid polyurethane foamsflame-retardant coatingpoly acrylamide hydrogelMXenenanocomposites |
| spellingShingle | Bin Chen Lizhong Yang Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating International Journal of Molecular Sciences rigid polyurethane foams flame-retardant coating poly acrylamide hydrogel MXene nanocomposites |
| title | Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating |
| title_full | Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating |
| title_fullStr | Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating |
| title_full_unstemmed | Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating |
| title_short | Enhanced Flame Retardancy of Rigid Polyurethane Foams by Polyacrylamide/MXene Hydrogel Nanocomposite Coating |
| title_sort | enhanced flame retardancy of rigid polyurethane foams by polyacrylamide mxene hydrogel nanocomposite coating |
| topic | rigid polyurethane foams flame-retardant coating poly acrylamide hydrogel MXene nanocomposites |
| url | https://www.mdpi.com/1422-0067/23/20/12632 |
| work_keys_str_mv | AT binchen enhancedflameretardancyofrigidpolyurethanefoamsbypolyacrylamidemxenehydrogelnanocompositecoating AT lizhongyang enhancedflameretardancyofrigidpolyurethanefoamsbypolyacrylamidemxenehydrogelnanocompositecoating |