SU956504A1 - Light stabilizer for polystyrene - Google Patents

Description

{54) POLYSTYRENE LAMP STABILIZER

The invention relates to the stabilization of polymers, specifically to light stabilizers of polystyrene. Polystyrene is widely used for making films, structural materials and various products. However, as is well known, polystyrene is unstable to the action of UV irradiation, which significantly shortens the service life of products. At present, 2- (2-hydroxy-5-methiLendle) -ben-zotriazole is widely used as a polystyrene stabilizer (Tinuvin P, Benazole l) C. The disadvantage of this compound is that the stabilization effect is achieved at relatively high co-concentrations (3 wt.%). The use of a light stabilizer in such quantities reduces the physicochemical properties of the polymer and, in addition, increases the cost of polymer products, complicates the process of obtaining

not

--- p / CH xCgHs

and L &

  Zn

{Compound W)

Syc

polymer concentrates and its processing. In addition, this stabilizer is capable of; sublimation at. This leads to a decrease in its content in the polymer during processing (200-250 ° C) or prolonged use of products from polystyrene, as a result of which its stabilizing effect decreases with time. Isolation. Tinuvina II causes air pollution, as it is known, it is a physiologically active compound and has a harmful effect on the body. The use of complex compounds of transition bivalent metals on the basis of heterocyclic derivatives of azomethines, in particular, 5t / c (l-phenyl-3-methyl-4-phenyl-aminomethyl-4-phenylminomethyl-zinc-5-zolonate) zinc, is known as polystyrene light stabilizers.

6wc (1-methyl-2-chloro-3-formyl-4-phenylaminomethylene-b-pyrrolonate) zinc

OHtv, / CH -j xCfiUs ttsCe- n iH ..- / dHO

V./Cl

.

 - r- 11II

- Zn

b:,. and 5 s (1 methyl-2. chloro-3-formyl-4-phenyl-Ottliv ./tU ljXeHs H However, these compounds do not provide a sufficient light-stabilizing effect. Conducted studies of their light-stabilizing ability showed that after 60 hours of irradiation polymer films containing these compounds , destruction of the polymer with a decrease in its molecular weight of up to 3 3-39% of the original occurs. The purpose of the invention is to increase the efficiency of the light stabilization of polystyrene. This goal is achieved using bis (1-phenyl-3-U1-methyl-4-B-aminomethylene-5- pyrazo l-thionate) of a metal of the general formula (... i:,. i6 "5 bN, M-Zn where R is C H, C as a polystyrene light stabilizer. Methods for preparing compounds of the specified formula, where I is R, 111 is R II , IV -, M Cu, V -, are described in I - b. When these compounds are used as light stabilizers of polystyrene, they are significantly smaller compared to analogs of the polymer end point. Molecular weight

Cl (Compound WL) vminomethylene-B-pyrrolthionate nickel W}. {XHN / (IHO (l (Compound L) decreases after irradiation in 60 hours to 40–76.9%. Production of polystyrene films with light stabilizer IM) is carried out by a watering method as follows. Example O, 02 g of the complex according to the invention is dissolved in 2 ml of dichloroethane, 2 g of polystyrene is added and the polystyrene is dissolved until complete. The solution obtained is applied with a silver on glass and dried to tacky. The light stabilizing effect is evaluated to the change in the molecular weight of polystyrene when irradiated with a DKsR-5000M lamp at a distance of 80 see from the source and at-SO C. Molecular weights are determined by viscometric. J Dependence of the molecular weight of full-triple films on insolation time (hour) with various stabilizers (M / Ml%), stabilizer concentration 0.5-1%, film thickness 0.04-0.005 Mk, shown in Table 1. For comparison, data are given for polystyrene stabilized by known compounds. From the table it can be seen that the compounds according to the invention are superior in light-stabilizing ability to known light-stabilizers by an average of 1.1-2.5 times. . Formula of the Invention The use of 6t (C (1-phenyl-3-meth-4-C-aminomethylene-5-pyrazolthionate) metal of general formula B.tH K. 1. XJ | 1 At 11 wwi .- where R is CH,,, CfeHj, N, and Cu as a polystyrene light stabilizer. Sources of information taken into account during the examinations 1. Auxiliary substances for polymeric materials.

Continuation of the table ed. Kb Piotrovsky and others. M., Himi, 1966, p. 59. 2. Swiss Patent 597578, cl. From 07 F.1 / 00, publ. 1976. 3, USSR Author's Certificate 737401, cl. C 07 F 1/08, 1977. 4, AD Garnovsky and others. A new type of sulfur-containing azomethine metal chelates. - Journal of General Chemistry, vol. 40, 1970, p. 2338. 5.Osipov O.A. et al. Complex compounds of metals with certain nitrogen-containing ligands. - Journal of General Chemistry, vol. 42, 1972, p. 926. 6. Alam LV / et al. Complexes with organic ligands. - Journal of Organic Chemistry, vol. 13, 1977, p. 863.

Claims (1)

Claim The use of bis (1-phenyl-3-methyl-4-th-aminomethylene-5-pyrazolthionate) metal of the General formula R-CH _?> C ₆ H ₅ , Μ-Ζη ⁴² , Νί ⁺² , C ₆ and ₅ Ci ⁴² , where as a light stabilizer of polystyrene.