کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1518998 1511627 2006 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Layered and intercalated hydrotalcite-like materials as thermal stabilizers in PVC resin
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد مواد الکترونیکی، نوری و مغناطیسی
پیش نمایش صفحه اول مقاله
Layered and intercalated hydrotalcite-like materials as thermal stabilizers in PVC resin
چکیده انگلیسی

In the light of the accepted mechanism of thermal stabilization of PVC by layered double hydroxides (LDHs), the layer cations and interlayer counterions in LDHs were tailored to give MgZnAl-CO3-LDH and MgZnAl-maleate-LDH. These materials were characterized by XRD, FT-IR, and TG–DTA. The thermal stability of PVC composites containing different LDH additives was tested in sheets having a thickness of about 1 mm. The results showed that compared with MgAl-CO3-LDH, MgZnAl-CO3-LDH enhances the thermal stability of PVC in terms of both long-term stability and early coloring. After intercalation of maleate in the LDH by reaction of maleic acid with the MgZnAl-CO3-LDH precursor, the interlayer distance increases from 0.75 to 1.11 nm. Since Cl− promotes the autocatalytic dehydrochlorination of PVC, which is responsible for its degradation, an increased interlayer distance should facilitate entry of Cl− into the interlayer galleries and inhibit the decomposition of PVC. In addition, maleic acid has a conjugated C=C double bond which can react with double bond formed in the dehydrochlorination of PVC and thus further inhibit the autocatalytic degradation reaction. The results show that the early coloring of PVC is markedly improved and the long-term stability slightly reduced by addition of the MgZnAl-maleate-LDH.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Physics and Chemistry of Solids - Volume 67, Issues 5–6, May–June 2006, Pages 998–1001
نویسندگان
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