KMT MDH compare with Japan grade

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, XK-10000SS/99, Japan magnesium hydroxide S-6, and 5P-C mechanical properties, finally the test result shows the tensile strength of XK-10000SN/99 is 15.3Mpa, the elongation at break is 204, the melt index is 0.3, and the oxygen index is 33; the tensile strength of XK-10000SS/99 is 16.25Mpa, The elongation at break is 190, the melt index is 0.45, and the oxygen index is 33; the tensile strength of Japan magnesium hydroxide S-6 is 12.5Mpa, The elongation at break is 211, the melt index is 1.9, and the oxygen index is 30; the tensile strength of Japan magnesium hydroxide 5P-C is 13Mpa, The elongation at break is 190, the melt index is 1.4, and the oxygen index is 32;

Key words: halogen free flame retardant formula, magnesium hydroxide, EVA based formulation

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 and XK-10000SS/99, particle size of 10000 mesh, from KMT INDUSTRIAL HK LIMITED; S-6 and 5P-C, particle size is 10000 mesh, from Japan.

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 Four grade magnesium hydroxide powders

Table 1. Fire retardant ingredients used in this study

	XK-10000SN/99	XK-10000SS/99	S-6	5P-C
Test conditions	23℃,40%	23℃,40%	23℃,40%	23℃,40%
Particle size (D50)	1.5um	1.6um	1.285um	1.4um
Surface coated or not	coated	coated	coated	coated

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 XK-10000SS/99 is 16.25 MPA, and that of S-6 is 12.5 MPA, and that of 5P-C is 13 MPA.

Table 2.

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 204, and that of XK-10000SS/99 is 190, and that of S-6 is 211, and that of 5P-C is 190. XK-10000SN/99 and XK-10000SS/99 is a fibre structure with high tensile strength and low elongation at break, which can be improved by surface modification. S-6 and 5P-C is a hexagonal crystal structure with the advantage of higher elongation at break.

Table 3.

2.4 Comparison of melting index of four 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 XK-10000SS/99 is 0.45, and that of S-6 is 1.9,and that of 5P-C is 1.4..

The melting index of XK-10000SN/99 is lower than that of S-6, that can be improved by selecting the melting index of the substrate..

2.5 Comparison of Oxygen Index between four 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 XK-10000SS/99 has a limiting oxygen index of 33, and S-6 has a limiting oxygen index of 30, and5P-C has a limiting oxygen index of 32.

XK-10000SN/99 has three points higher oxygen index than S-6 and better flame retardancy.

3. Conclusion and discussion

3.1 Elongation at break (%): S-6 is the best one, and then XK-10000SN/99 is better.

3.2 Tensile Strength (MPa): XK-10000SS/99 is the best one,, and then XK-10000SN/99 is better.

3.3 LOI (120*10*4): XK-10000SN/99 and XK-10000SS/99 is best.

3.4 MFI(190℃.5KG): S-6 is the best one, and then 5P-C is better.

Company Profiles…

KMT INDUSTRIAL HK LIMITED, headquartered in Gansu, China, research and manufacturer magnesium hydroxide, natural brucite powder. www.kmtindustrial.com

Contact: ara@kmtindustrial.com

KMT MDH compare with Japan grade