Facile Synthesis of Di-Mannitol Adipate Ester-Based Zinc Metal Alkoxide as a Bi-Functional Additive for Poly(Vinyl Chloride)

Abstract

A new di-mannitol adipate ester-based zinc metal alkoxide (DMAE-Zn) was synthesized as a bi-functional poly(vinyl chloride) (PVC) thermal stabilizer for the first time. The materials were characterized with Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). Characterization results confirmed the formation of Zn–O bonds in DMAE-Zn, and confirmed that DMAE-Zn had a high decomposition temperature and a low melting point. The thermal stability of DMAE-Zn on PVC also was tested by a conductivity test, a thermal aging test, and a UV-visible spectroscopy (UV-VIS) test. PVC stabilized by DMAE-Zn had a good initial color and excellent long-term stability. UV-VIS also showed that the conjugated structure in PVC stabilized by DMAE-Zn was almost all of the triene, suggesting that the addition of DMAE-Zn would suppress the formation of conjugated structures above tetraene. The dynamic processing performance of PVC samples tested by torque rheometer indicated that, having a good compatibility with PVC chains in the amorphous regions, DMAE-Zn contributed a good plasticizing effect to PVC. DMAE-Zn thus effectively demonstrates bi-functional roles, e.g., thermal stabilizers and plasticizers to PVC. Furthermore, FT-IR, a HCl absorption capacity test, and a complex ZnCl2 test were also used to verify the thermal stability mechanism of DMAE-Zn for PVC.

Incorporation of flame retardancy in bio‐resourced mannitol based curing agent for clear pressure‐sensitive adhesive

“…This ester group undergoes uncapping when reacted with methanol and sodium result to formation of the -OH group with a strong contributory peak at 3359 cm −1 . The peak at 2904 cm −1 indicates -CH 2 group and confirms its inertness in the reaction 43,44. The sharp peak of C-O at 1055 cm −1 for BMDM and MDM strengthens the proposed chemical reaction.…”

Enhancing the Initial Whiteness and Long-Term Thermal Stability of Polyvinyl Chloride by Utilizing Layered Double Hydroxides with Low Surface Basicity

“…At 60 min of aging, the PVC with TS-Zn stabilizer turned black, a phenomenon known as “zinc burning.” This was due to the absorption of HCl released from PVC decomposition by zinc stearate in TS-Zn, leading to the formation of ZnCl2, which catalytically accelerated PVC decomposition [ 12 ]. PVC composites with MgAl2.0/TS-Zn had an initial chromaticity index b* of 7.62 and, although its initial whiteness was not as good as PVC stabilized with TS-Zn only, its color did not turn yellow until 60 min of aging and did not turn brown until 105 min, suggesting that MgAl2.0 improved the long-term thermal stability of PVC.…”

“…However, the traditional thermal stabilizers, such as lead/cadmium salts and organotin, pose health and environmental hazards, leading to regulations such as EU 76/769/EEC, WEEE, and RoHS that require the use of non-toxic, environmentally friendly, and efficient thermal stabilizers [ 8 ]. Thermal stabilizers of β-diketone compounds, zinc stearate, and LDHs show great potential as practical alternatives [ 4 , 9 , 10 , 11 , 12 , 13 , 14 ].…”

Trends and prospects for thermal stabilizers in polyvinyl chloride

“…Finally, the capacity for neutralizing HCl was calculated by the volume of NaOH solution used. [ 67 ] The two methods listed above are the solid and liquid phase methods, respectively. However, both of them have their flaws.…”