Effect of 1,2,3-Trichloropropane as Tri-Functional Monomer on Thermophysical Properties of Poly(ethylene tetrasulfide)
نویسندگان
چکیده مقاله:
In this study, the effect of 1,2,3-trichloropropane (TCP) as trifunctional monomer on thermophysical properties of synthesized poly(ethylene tetrasulfide) (PETS) is investigated. To this end, different amounts of TCP (0-40 mol. % of halide-containing monomer) were incorporated into the structure of polysulfide polymer via interfacial condensation polymerization. Measurement of gel, fraction showed that by the introduction of only 10 mol. % of TCP, synthesized structure is almost crosslinked. The X-Ray Diffraction (XRD) results revealed that all samples are semi-crystalline whereas the crystallinity of samples strongly depends on the amount of TCP. All samples showed a glass transition temperature (Tg) less than 0 °C followed by melting temperature (Tm). Higher amountof crosslinking monomer resulted in higher Tg while Tm and heat of fusion (ΔHm) were reduced. According to ThermoGravimetric Analysis (TGA) results, all samples exhibited a two-stage degradation process. Although, the introduction of 10 mol. % TCP into the structure of PETS resulted in lower thermal stability of obtained polymer, adding higher amounts of TCP led to the higher thermal stability of polymers.
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عنوان ژورنال
دوره 39 شماره 2
صفحات 241- 247
تاریخ انتشار 2020-04-01
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