تحضير وتشخيص بعض مركبات الكبريت غير متجانسة الحلقة و دراسة تأثيرها كمثبطات لهب لراتنجي البولي استر غير المشبع والأيبوىكسي

Preparation and Characterization of some hetero cyclic sulfur compounds and studies its effect as flame retardant for unsaturated polyester and epoxy resins

In this study, ten heterocyclic organic compounds were prepared and characterization by 1HNMR, 13CNMR, FT-IR and CHN . They were studied on effectiveness in inhibiting the flame and increasing the resistance to ignition of the unsaturated polyester and epoxy resins, and these additives are:
1. Additive A1: (5,6-diphenyl-6H-1,3,4-thiadiazin-2-amine)
2.Additive A2: (Pentane-2,3,4-trione3-[ (5,6-diphenyl-6H-1,3,4-thiadiazin -2-yl) hydrazine ] )
3. Additive A3: (5-[(z)-(5,6-diphenyl-6H-1,3,4-thiadiazin-2-yl)diazenyl]-4,6 dimethyl-2H-1,3-thiazin-2-amine)
4. Additive A4: (6-[(5,6-diphenyl-6H-1,3,4-thiadiazin-2-yl)diazenyl]-5,7 dimethyl -1,3,4-thiadiazepin-2-amine)
5. Additive A5: (5,6-diphenyl-2-[(Z)-(2,4,6-trimethyl-2H-1,3-thiazin-5-yl) diazenyl]-6H-1,3,4-thiadiazine)
6. Additive A6: ((4Z,6E)-6-((Z)-(5,6-diphenyl-6H-1,3,4-thiadiazin-2-yl) diazenyl )-5,7-dimethyl-2,3-dihydro-1,4-thiazepine -3-carboxylic acid)
7. Additive A7: (5-(1,4-phenylene)bis (1,3,4-thiadiazinol-2-amine)
8. Additive A8: (2,2-(1,4-phenylene-bis-(1,3,4-thiadiazole) -5yl) bis (1,2-benzisothiazol-3(2H)-one) 1,1,1,1,-tetraoxide)
9.Additive A9: (2,2-(1,4-phenylene)bis(4,5-dihydro-1,thiazole-4-carboxylic acid)
10. Additive A10: (5,5 -[1,4-phenylene bis(4,5-dihydro-1.3-thiazole-2,4-diyl) bis (1,3,4-thiadiazol-2-amine))
Three sheets in three dimensions (13 x 13 x 0.3 cm) of unsaturated polyester and epoxy resin with the above additives were prepared with the weight percentages (0.2, 0.4, 0.6 and 0.8%) and these sheets were cut according to the (ASTM) standards .
The study included a series of standard tests used to measure the obstruction of the flame and increase the resistance of ignition. Two
standard methods were chosen to demonstrate the efficiency of the additives in blocking the abrasion of the unsaturated polystyrene resin and the epoxy resins.
1. Method of measuring the limiting oxygen index (LOI) using the approved method of testing (ASTM: D-2863).
2. The method of measuring the rate of burning (R.B), the extent of burning (E.B) and the time of burning (TB) through the approved method of examination (ASTM: D-635).
The results of the above measurements showing that the additives referred to the above were significant effectiveness in inhibition of the flame and increased the ignition resistance of unsaturated polyester resin and epoxy resins. The efficiency of additives was ordered as.
A10 > A4 > A8 > A3 > A7 > A6 > A5 > A2 > A1 > A9
The study was showed that a good flame retardant and obtained in all percentages of additives of obtained a self-extinguishing in percentage 0.2% for each additives A4 and A10, self-extinguishing in percentage 0.4 % for the additives A3 and A10, and Non-Burning occurring in the percentage 0.4 % for the additives A4 and A10, so the percentage 0.6% for the additive A8 for Polyester resin also 0.6 % for the additives A4 and A10 for epoxy resins.