Poly(vinyl chloride) derivatives as stabilizers against photodegradation

Peer review under responsibility of Taibah University.

Figures & data

Table

Compound	Structure of the polymers
PVC
P1
P2
P3
P4

Fig. 1 Change in IR spectrum of PVC film (30 μm) in the presence of P3 polymer.

Scheme 1 Some of the photooxidation processes of PVC; reactions of radical B with molecular oxygen, akin to those of radical A, would give rise to chloroketone, chloroalcohol and chlorohydroperoxide moieties; further reactions of such reactive functionalities may lead to chain cleavage and reduction in molecular weight.

Fig. 2 The relationship between the carbonyl index and irradiation time for PVC films and modified PVC films (30 μm thickness).

Fig. 3 The relationship between the polyene index and irradiation time for PVC films and modified PVC films (30 μm thickness).

Fig. 4 The relationship between the hydroxyl index and irradiation time for PVC films and modified PVC films (30 μm thickness).

Fig. 5 Changes in the viscosity-average molecular weight $({\overline{M}}_v)$ during irradiation of PVC films (30 μm) (control) and modified PVC films (30 μm thickness).

Fig. 6 Changes in the main chain scission (S) during irradiation of PVC films (30 μm) (control) and with modified PVC films (30 μm thickness).

Fig. 7 Changes in the degree of deterioration (α) during irradiation of PVC films (30 μm) (control) and modified PVC films (30 μm thickness).

Fig. 8 Microscopic images of P3 samples.

Table 1 Quantum yield (Φ_cs) for the chain scission for PVC films (30 μm) thickness with and modified polymers after 250 h irradiation time.

Additive (0.5 wt%)	Quantum yield of main chain scission (Φcs)
P1	4.79E−08
P2	5.33E−08
P3	6.71E−08
P4	7.50E−08
PVC (blank)	8.62E−05