Title Page
Contents
Abstract 6
I. Introduction 7
II. Experimental 12
2.1. Materials 12
2.2. Preparation of PMSQ aerogel monolith 12
2.3. Preparation of the SRPUF/PMSQ aerogel composite 13
2.4. Characterization 14
III. Results and discussion 16
3.1. Effects of acid-catalyzed reaction and ageing times 16
3.2. Effects of fluoric surfactant FC-4432 20
3.3. Thermal conductivity of PMSQ aerogels 23
3.4. Preparation of SRPUF/aerogel composites 27
3.5. Thermal conductivity of SRPUF/aerogel composites 30
3.6. Sound insulating ability and hydrophobicity 32
IV. Conclusion 35
V. Reference 37
Table 1. Various compositions for optimizing acid-catalyzed hydrolysis reaction and ageing times 18
Table 2. Bulk densities, thermal conductivities, and sound absorption coefficients of SRPUF/aerogel composites 29
Figure 1. Schematic illustration of preparation of crackless PMSQ aerogels and SRPUF/aerogel composites. 14
Figure 2. Photographic images of PMSQ aerogels prepared by varying the acid-catalyzed hydrolysis reaction time: (a) 2 h, (b) 10 h, (c) 20 h, and (d) 40 h. 17
Figure 3. SEM microphotographs of PMSQ aerogel prepared by varying the acid-catalyzed hydrolysis reaction time: (a) 2 h, (b) 10 h, (c) 20 h, and (d) 40 h. 20
Figure 4. Photographs of PMSQ aerogel with different amounts of surfactant FC-4432: (a) 0 g, (b) 0.04 g, and (c) 0.08 g. 22
Figure 5. SEM microphotographs of PMSQ aerogel with different amounts of surfactant FC-4432: (a) 0 g, (b) 0.04 g, and (c) 0.08 g. 25
Figure 6. Thermal conductivities of PMSQ aerogel with different amounts of surfactant FC-4432: (a) 0 g, (b) 0.04 g, and (c) 0.08 g. 26
Figure 7. Surface images of SRPUF/aerogel composites with different amounts of PMSQ aerogel: (a) 0 phr, (b) 10 phr, (c) 18 phr, (d) 45 phr, (e) 63 phr, and (f) 109 phr. 28
Figure 8. SEM microphotographs of cells for (a) neat SRPUF and (b-d) SRPUF/aerogel composites (PUFA45). 30
Figure 9. Thermal conductivities of neat SRPUF and SRPUF/aerogel composites with respect to the amount of PMSQ aerogel. 32
Figure 10. Sound absorption coefficients of neat SRPUF and SRPUF/aerogel composites. 33
Figure 11. water contact angles images of a) neat SRPUF, b) SRPUF/aerogel composite, and c) the PMSQ aerogel 34