——H5IV and XK-10000SN/99 compare
By:
Ara king and Frank Chen
KMT INDUSTRIAL HK LIMITED
www.kmtindustrial.com
Abstract :
Formulation was: EVA (7470K) 35%, compatibilizer 5%, antioxidant 0.175%, magnesium hydroxide 60%; Test conditions: 23℃, 40%; and we want to compare two grades XK-10000SN/99 and H5IV mechanical properties, finally the test result shows the tensile strength of XK-10000SN/99 is 16.3Mpa, the elongation at break is 190, the melt index is 0.3, and the oxygen index is 33; the tensile strength of H5IV is 14.8Mpa, The elongation at break is 210, the melt index is 0.52, and the oxygen index is 31.5.
Key words: halogen free flame retardant formula, magnesium hydroxide
1. Materials and Testing
1.1Materials prepare
Ethylene-vinyl acetate copolymer (EVA), grade 7470K, vinyl acetate (vA) content is 26%, from Formosa Plastics Group; Magnesium hydroxide (MH) XK-10000SN/99, particle size of 10000 mesh, from KMT INDUSTRIAL HK LIMITED; Magnesium hydroxide (MH) H5IV, particle size is 10000 mesh, from JM Huber Corporation.
Banbury, Plate Curing Press; Mould; SY-6210-A Electronic Pulling Force Machine; Oxygen Index Meter;
1.2 Preheat the Banbury to 100 °C-120 °C, the mixing time is 30 minutes, the mixing temperature is 200 ± 10 °C
Put the dough into the mould which is preheated well in advance (the thickness of the mould frame is 1 ± 0.1 mm), then use plate Curing Press tabletting (prepress: 10MPA, pressure: 10-15mpa, temperature: 220 °C, preheat for 2 Min) , After tabletting cooled to 40-50 °C and got the samples.
1.3 Composite Standard Test Strips made from dies, the tensile properties were tested on SY-6210-A electronic tensile machine with a tensile speed of 250 mm/min and sample size of 120 * 10 * 1mm (GB/T 32129-2015 standard for halogen-free flame retardant cable materials for wire and cable).
1.4 Testing of combustion performance (GB/T 2406.2—2009)
2. Results and Discussion
2.1 Two grade magnesium hydroxide powders
Table 1. Fire retardant ingredients used in this study
| XK-10000SN/99 | H5IV | |
| Test conditions | 23℃,40% | 23℃,40% |
| Particle size (D50) | 1.5um | 1.89um |
| Surface coated or not | coated | coated |
2.2 Test result of tensile strength
Table 2 shows under the formula: EVA (7470K) is 35%, compatibilizer 5%, antioxidant 0.175%, Magnesium hydroxide 60% in the same composition system; The results show that the tensile strength of XK-10000SN/99 is 15.5 MPA, and that of H5IV is 14.8 MPA.
Table 2.
| Formula | 1 | 5 |
| EVA(7470K) | 35% | 35% |
| Compatibilizer | 5% | 5% |
| Antioxidant | 0.175% | 0.175% |
| MDH XK-10000SN/99 | 60% | |
| MDH H5IV | 60% | |
| Tensile Strength (MPa) | 16.3 | 14.8 |
2.3Comparison of Elongation at break of two grades in EVA System
According to Table 3, the content of EVA (7470K) was 35%, compatibilizer 5%, antioxidant 0.175% and Magnesium hydroxide 60%; The results show that the elongation at break of XK-10000SN/99 is 190, and that of H5IV is 210. XK-10000SN/99 is a fibre structure with high tensile strength and low elongation at break, which can be improved by surface modification. H5IV is a hexagonal crystal structure with the advantage of higher elongation at break.
Table 3
| Formula | 1 | 5 |
| EVA(7470K) | 35% | 35% |
| Compatibilizer | 5% | 5% |
| Antioxidant | 0.175% | 0.175% |
| MDH XK-10000SN/99 | 60% | |
| MDH H5IV | 60% | |
| Elongation at break (%) | 190 | 210 |
2.4 Comparison of melting index of two grades in EVA System
According to Table 4, the content of EVA (7470K) was 35%, compatibilizer 5%, antioxidant 0.175% and Magnesium hydroxide 60%
The results show that the melting index of XK-10000SN/99 is 0.3 and that of H5IV is 0.52.
The melting index of XK-10000SN/99 is lower than that of H5IV. that can be improved by selecting the melting index of the substrate.
Table 4
| Formula | 1 | 5 |
| EVA(7470K) | 35% | 35% |
| Compatibilizer | 5% | 5% |
| Antioxidant | 0.175% | 0.175% |
| MDH XK-10000SN/99 | 60% | |
| MDH H5IV | 60% | |
| MFI(190℃.5KG) | 0.3 | 0.52 |
2.5 Comparison of Oxygen Index between two grades in EVA System
According to Table 5, the content of EVA (7470K) was 35% , compatibilizer 5% , antioxidant 0.175% and Magnesium hydroxide 60%
The results show that XK-10000SN/99 has a limiting oxygen index of 33, and H5IV has a limiting oxygen index of 31.5.
XK-10000SN/99 has two points higher oxygen index than H5iv and better flame retardancy.
Table 5
| Formula | 1 | 5 |
| EVA(7470K) | 35% | 35% |
| Compatibilizer | 5% | 5% |
| Antioxidant | 0.175% | 0.175% |
| MDH XK-10000SN/99 | 60% | |
| MDH H5IV | 60% | |
| LOI (100*10*1mm) | 33 | 31.5 |
3. Conclusion
| Formula | 1 | 5 |
| EVA(7470K) | 35% | 35% |
| Compatibilizer | 5% | 5% |
| Antioxidant | 0.175% | 0.175% |
| MDH XK-10000SN/99 | 60% | |
| MDH H5IV | 60% | |
| MFI(190℃.5Kg) | 0.3 | 0.52 |
| Elongation at break (%) | 190 | 210 |
| Tensile Strength (MPa) | 16.3 | 14.8 |
| Test Conditions | 23℃,40% | 23℃,40% |
| Particle size ( D50/um) | 1.3-1.6 | 1.89 |
| LOI (100*10*1mm) | 33 | 31.5 |
According to the above experimental data we can see that:
3.1 under this formulation: H5IV has advantages over XK-10000SN/99:
3.11: High Melt Index
3.12: High Elongation at break
3.2 under this formulation: H5IV compared to XK-10000SN/99 disadvantages:
3.21: Low tensile strength
3.22: Low LOI
Company Profiles…
KMT INDUSTRIAL HK LIMITED, headquartered in Gansu, China, research and manufacturer magnesium hydroxide, natural brucite powder. www.kmtindustrial.com
