Introduction
Experimental
Syntheses
Synthesis of metasilicic acid
Reaction of metasilicic acid with glycidol
Reactions of semi-product MSA:GL = 1:4 with ethylene carbonate
Analytical methods
Substance | Retention time (min) | Coefficients from Eq. (3) | Correlation coefficient | |
---|---|---|---|---|
a
|
b
| |||
Cyclohexanone | 8.53 | – | – | |
ED | 13.64 | 2.7939 | 0.1006 | 0.9982 |
DEG | 17.47 | 2.4917 | 0.1694 | 0.9988 |
TEG | 20.83 | 2.6634 | 0.2392 | 0.9987 |
TeEG | 25.95 | 4.4556 | 0.2740 | 0.9993 |
Physical properties of oligoetherols
Obtaining of polyurethane foams
Properties of foams
Results and discussion
Synthesis of oligoetherol
Reagents | Initial molar ratio of reagents | Elemental analysisa
| Molar ratio MSA:GL:ethylene groups in oligoetherol | Hydroxyl number (mg KOH/g) | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Calculated from mass balance | Found | |||||||||
Si | C | H | Si | C | H | Calc. | Found | |||
MSA:GL:EC | 1:4:3 | 2.51 | 46.83 | 7.98 | 2.32 | 46.34 | 8.38 | 1:10:6.8 | 602.6 | 806.8 |
ED | DEG | TEG | TeEG |
∑
|
---|---|---|---|---|
7.9 | 9.0 | 2.4 | 0.6 | 19.9 |
Refractive index | Density (g/cm3) | Viscosity (mPa s) | Surface tension (N/m) × 103
|
---|---|---|---|
1.4790 | 1.2503 | 33,442 | 0.60 |
Obtaining polyurethane foams and their properties
Composition no. | Composition (g/100 g of oligoetherols) | Foaming process | Characteristics of foam immediately after formation | ||||||
---|---|---|---|---|---|---|---|---|---|
Isocyanate | Water | Catalyst TEA | Silicone | Molar ratio NCO/OH | Cream time (s) | Rise time (s) | Tack-free time (s) | ||
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
1 | 132 | 1 | 2.7 | 23 | 08 | 28 | – | – | Low level of foaming |
2 | 132 | 2 | 3.2 | 2.3 | 0.8 | 49 | 60 | – | Rigid, fast growing |
3 | 132 | 3 | 2.7 | 2.3 | 0.8 | 25 | 44 | 1 | Large pores |
4 | 148 | 4 | 2.7 | 2.3 | 0.8 | 23 | 10 | 1 | Semirigid, under-crosslinked |
5 | 160 | 6 | 2.7 | 2.3 | 0.8 | 25 | 19 | 28 | Semirigid, fragile |
6a
| 132 | 2 | 1.6 | 2.3 | 0.8 | 30 | 25 | 1 | Rigid, regular pores |
7 | 184 | 4 | 2.2 | 2.3 | 1.1 | 39 | 27 | 1 | Large pores, fragile |
8 | 184 | 4 | 1.6 | 2.3 | 1.1 | 40 | 42 | 120 | Cracks during growing, fragile |
9 | 184 | 4 | 1.3 | 2.3 | 1.1 | 51 | 23 | 30 | Cracks during growing, soft |
10a
| 184 | 4 | 0.5 | 3.1 | 1.1 | 58 | 63 | 2 | Rigid, regular pores |
Foam | No. composition according to Table 6
| Density (kg/m3) | Absorption of water (% wt) after | Dimensional stability (%) in temperature 150 °C | Heat conductance coefficient (W/m K) | |||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Length change (%) | Width change (%) | Hight change (%) | ||||||||||
5 min | 3 h | 24 h | 20 h | 40 h | 20 h | 40 h | 20 h | 40 h | ||||
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 |
Before exposure | 6 | 95.5 ± 3.2 | 3.82 ± 0.60 | 4.07 ± 0.15 | 6.68 ± 0.26 | −0.42 | −0.58 | −0.67 | −0.67 | −0.39 | −1.75 | 0.0368 ± 0.0000 |
10 | 96.8 ± 2.9 | 2.77 ± 0.08 | 4.52 ± 0.13 | 8.17 ± 0.40 | 0.96 | 1.44 | 4.93 | 5.97 | 3.88 | 4.61 | 0.0249 ± 0.0001 | |
After exposure in 150 °C | 6 | 131.0 ± 5.2 | 2.47 ± 0.07 | 3.97 ± 0.13 | 5.87 ± 0.44 | – | – | – | – | – | – | 0.0498 ± 0.0008 |
10 | 130.7 ± 4.3 | 1.77 ± 0.07 | 3.03 ± 0.09 | 3.89 ± 0.32 | – | – | – | – | – | – | 0.0487 ± 0.0002 | |
After exposure in 175 °C | 6 | 272.2 ± 5.6 | 3.13 ± 0.43 | 4.21 ± 0.12 | 7.91 ± 0.25 | – | – | – | – | – | – | 0.0734 ± 0.0025 |
10 | 242.0 ± 6.2 | 3.00 ± 0.24 | 3.89 ± 0.30 | 4.94 ± 0.38 | – | – | – | – | – | – | – |
Foam | No. composition according to Table 6
| Mass loss in %wt after exposition in month | Compressive strength (MPa) | Change of compressive strength in (%) | Oxygen index | Flame zone (mm) | Flame rate (mm/s) | Mass loss upon flaming (%) | Remarks |
---|---|---|---|---|---|---|---|---|---|
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |
Before exposure | 6 | – | 0.486 | – | 21.1 | 150 | 2.0 | 80 | Melts, drips |
10 | – | 0.167 | – | 21.9 | 21 | 0.7 | 16.8 | Burns slowly, extinguish | |
After exposure in 150 °C | 6 | 24.0 | 1.275 | +144.4 | 24.4 | 105 | 2.1 | 2.45 | Burns in flame, extinguish out of flame |
10 | 16.7 | 0.321 | +79.1 | 23.4 | 0 | 0 | 5.62 | ||
After exposure in 175 °C | 6 | 36.5 | 5.051 | +698.4 | 36.0 | 0 | 0 | 0.47 | No burns in flame |
Foam |
T
5% (°C) |
T
10% (°C) |
T
25% (°C) |
T
50% (°C) |
T
max (°C) |
---|---|---|---|---|---|
Before exposure | 167 | 221 | 265 | 361 | 260, 390 |
After exposure in 150 °C | 242 | 277 | 341 | 469 | 345 |
After exposure in 175 °C | 77 | 291 | 412 | >600 | 350–380 |
Foams | Element | ||
---|---|---|---|
C | H | N | |
Before exposure | 59.61 | 6.60 | 7.07 |
After exposure in 150 °C | 61.45 | 5.50 | 8.16 |
After exposure in 175 °C | 61.67 | 4.37 | 9.36 |