Prediction of the long-term outdoor weathering of poly(vinyl chloride)

As poly(vinyl chloride) (PVC) photodegrades with long-term exposure to ultraviolet radiation, it is desirable to develop methods that enhance the photostability of PVC. In this study, new aromatic-rich diorganotin(IV) complexes were tested as photostabilizers in PVC films. The diorganotin(IV) complexes were synthesized in 79–86% yields by reacting excess naproxen with tin(IV) chlorides. PVC films containing 0.5 wt % diorganotin(IV) complexes were irradiated with ultraviolet light for up to 300 h, and changes within the films were monitored using the weight loss and the formation of specific functional groups (hydroxyl, carbonyl, and polyene). In addition, changes in the surface morphologies of the films were investigated. The diorganotin(IV) complexes enhanced the photostability of PVC, as the weight loss and surface roughness were much lower in the films with additives than in the blank film. Notably, the dimethyltin(IV) complex was the most efficient photostabilizer. The polymeric film containing this complex exhibited a morphology of regularly distributed hexagonal pores, with a honeycomb-like structure—possibly due to cross-linking and interactions between the additive and the polymeric chains. Various mechanisms, including direct absorption of ultraviolet irradiation, radical or hydrogen chloride scavenging, and polymer chain coordination, could explain how the diorganotin(IV) complexes stabilize PVC against photodegradation.

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Long-term performance of poly(vinyl chloride) cables. Part 1: Mechanical and electrical performances

Polymer Degradation and Stability ◽

10.1016/j.polymdegradstab.2007.01.005 ◽

2007 ◽

Vol 92 (4) ◽

pp. 617-629 ◽

Cited By ~ 46

Author(s):

M. Ekelund ◽

H. Edin ◽

U.W. Gedde

Keyword(s):

Vinyl Chloride ◽

Poly Vinyl Chloride ◽

Long Term Performance ◽

Term Performance

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Mechanism of Action of Titanium Dioxide Pigment in the Photodegredation of Poly(Vinyl Chloride) and Other Polymers

Progress in Reaction Kinetics and Mechanism ◽

10.3184/007967401103165316 ◽

2001 ◽

Vol 26 (4) ◽

pp. 337-374 ◽

Cited By ~ 13

Author(s):

Terence J. Kemp ◽

Robin A. McIntyre

Keyword(s):

Titanium Dioxide ◽

Vinyl Chloride ◽

Wide Band ◽

Transition Metal Ions ◽

Short Review ◽

Band Gaps ◽

Chemical Action ◽

Alkyd Resins ◽

Poly Vinyl Chloride

The extensive use of titanium dioxide as a pigment and optical agent in polymers, particularly poly(vinyl chloride), polyethylene and alkyd resins, has prompted many investigations of the various deleterious effects (loss of gloss and mechanical properties, chalking, pinking) of long-term exposure to sunlight of the pigmented polymers. This short review summarises the fundamental semiconductor processes undergone by TiO2 on UV irradiation and the consequent chemical action of the reactive intermediates so generated. It also describes the strategies developed to counteract photodegradation induced by TiO2, in particular its encapsulation in a coating by near-UV transparent metal oxides, such as Al2O3 and SiO2, with wide band gaps. The effects of doping TiO2 with transition metal ions are also noted.

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Synthesis and Study of Zinc Orotate and its Synergistic Effect with Commercial Stabilizers for Stabilizing Poly(Vinyl Chloride)

Polymers ◽

10.3390/polym11020194 ◽

2019 ◽

Vol 11 (2) ◽

pp. 194 ◽

Cited By ~ 5

Author(s):

Feng Ye ◽

Qiufeng Ye ◽

Haihua Zhan ◽

Yeqian Ge ◽

Xiaotao Ma ◽

...

Keyword(s):

Thermal Stability ◽

Synergistic Effect ◽

Vinyl Chloride ◽

Zinc Stearate ◽

Precipitation Method ◽

Long Term Stability ◽

Poly Vinyl Chloride ◽

Initial Color ◽

Thermal Stability Of

Zinc orotate (ZnOr2), which is a new kind of poly(vinyl chloride) (PVC) stabilizer, is prepared in this work through the precipitation method, and its impact on the thermal stability of PVC is measured by thermogravimetric analysis (TG), Congo red test, and discoloration test. The results exhibit that the thermal stability of PVC is positively enhanced after the addition of ZnOr2. In contrast with a commercial thermal stabilizer, zinc stearate (ZnSt2), a noteworthy improvement was observed that ZnOr2 could postpone the “zinc burning” of PVC. This is principally ascribed to the Or anion in the structure of ZnOr2 being able to absorb the HCl released by PVC, and to supersede unstable chlorine atoms in the structure of PVC. In addition, blending ZnOr2 with calcium stearate (CaSt2) in diverse mass ratios can significantly accelerate the thermal stability of PVC. Optimum performance was achieved with a CaSt2:ZnOr2 ratio of 1.8:1.2. Moreover, an outstanding synergistic effect can be observed when CaSt2/ZnOr2 is coupled with other commercial auxiliary stabilizers. The initial color and long-term stability of PVC including CaSt2/ZnOr2 is significantly increased when pentaerythritol (PER) is added, while dibenzoylmethane (DBM) can only improve its long-term thermal stability.

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A novel zinc-containing additive for the long-term thermal stabilization of poly(vinyl chloride)

Polymer Degradation and Stability ◽

10.1016/j.polymdegradstab.2014.05.009 ◽

2014 ◽

Vol 107 ◽

pp. 113-119 ◽

Cited By ~ 19

Author(s):

Guoan Chen ◽

Liqiang Gu ◽

Youwei Yao

Keyword(s):

Vinyl Chloride ◽

Thermal Stabilization ◽

Poly Vinyl Chloride

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Long-term heat stabilisation by (natural) polyols in heavy metal- and zinc-free poly(vinyl chloride)

Polymer Degradation and Stability ◽

10.1016/j.polymdegradstab.2005.04.027 ◽

2006 ◽

Vol 91 (1) ◽

pp. 52-59 ◽

Cited By ~ 29

Author(s):

Johan Steenwijk ◽

Rik Langerock ◽

Daan S. van Es ◽

Jacco van Haveren ◽

John W. Geus ◽

...

Keyword(s):

Heavy Metal ◽

Vinyl Chloride ◽

Poly Vinyl Chloride ◽

Heat Stabilisation

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Development and Investigation of Lanthanum Sulfadiazine with Calcium Stearate and Epoxidised Soyabean Oil as Complex Thermal Stabilizers for Stabilizing Poly(vinyl chloride)

Polymers ◽

10.3390/polym11030531 ◽

2019 ◽

Vol 11 (3) ◽

pp. 531 ◽

Cited By ~ 3

Author(s):

Qiufeng Ye ◽

Xiaotao Ma ◽

Bobin Li ◽

Zhe Jin ◽

Yingying Xu ◽

...

Keyword(s):

Thermal Stability ◽

Vinyl Chloride ◽

Calcium Stearate ◽

Gravimetric Analysis ◽

Thermal Stabilizer ◽

Poly Vinyl Chloride ◽

Water As Solvent ◽

Vis Spectroscopy ◽

Thermal Stability Of

Lanthanum sulfadiazine (LaSD) was synthesized from sulfadiazine and lanthanum nitrate using water as solvent under alkaline conditions, and was used as a novel rare earth thermal stabilizer to stabilize poly(vinyl chloride) (PVC). The structure of LaSD was characterized by elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR) and thermo- gravimetric analysis (TGA). The influence of lanthanum sulfadiazine with calcium stearate (CaSt2) and epoxidized soybean oil (ESBO) on stabilizing PVC was studied by using the Congo red test, oven discoloration test, UV-vis spectroscopy and thermal decomposition kinetics. The results showed that the addition of LaSD as a thermal stabilizer can significantly improve the initial whiteness and long-term stability of PVC. In addition, the synergies between LaSD, ESBO, and CaSt2 can provide outstanding improvement in the long-term thermal stability of PVC. When the ratio of LaSD/ESBO/CaSt2 is 1.8/0.6/0.6, its thermal stability time is 2193 s which is the best state for stabilizing PVC. Furthermore, comparing the reaction energy (Ea) and the variations in the conjugate double bond concentration in PVC samples, the order of thermal stability of PVC was PVC/LaSD/ESBO/CaSt2 > PVC/LaSD/ESBO > PVC/LaSD. The thermal stability mechanism of LaSD on PVC was studied by the AgCl precipitation method and FTIR spectrum. The results showed that the action of LaSD on PVC was achieved through replacing unstable chlorine atoms and absorbing hydrogen chloride.

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