CS226700B1 - Polymerizable light stabilizer of piperidine type and method of preparing same - Google Patents

Description

The invention relates to a polymerizable piperidine-type light stabilizer and a process for its preparation.

Sterically hindered amines are a modern class of plastic light stabilizers. A certain disadvantage of the low molecular weight substances of this class is their easy washability and toxicity.

The above-mentioned disadvantages are overcome by the present compound of the present invention, which is characterized in that itaconic acid dimethyl ester of formula I:

, cooch ₃

CH-COOCH2- (4-Amino-2,2,0,6-tetramethylpiperidine II) is treated with:

in methanol solution at 25 ° C for 24 hours and at reflux for 2 hours to give N- (2,2,6,6-tetraimethylpiperidyl) -4-methoxycarbonyl-γ-lactam of formula III:

CH.

H

\ ' ^CH \

YN CH-CO-CH ₃ CO ^7-CH ₃ h (not

Example 1

12.5 g (0.08 mol] of _4-amino-2,2) 6,6-ethylpiperidine Tetra ^I and 12.8 g (0.08 mol) of itaconic acid dimethyl ester in 40 ml of methanol was stirred 24 h at 25 C. The reaction mixture was then refluxed for 2 hours. Methanol was distilled off on a rotary evaporator and the solid residue dissolved in chloroform was extracted to remove the preferred amine. After distilling off the chloroform on a rotary evaporator, the crude product was crystallized from n-hexane. 12 g (53%) of white crystals 1.1 were obtained. 127 DEG-129 DEG. Analysis of C15H26N2O3

Molecular Weight: 282,39

calculated:

% C, 63.80;% H, 9.28;% N, 9.92.

found:

H, 9.51; N, 9.96.

IR (chloroform):

2950, 2930, 1740, 1690, 1370, 1390,

1170 cm ^-1

Example 1 a d 2

The polypropylene blend with 0.1% AO-4K antioxidant content, 0.15% calcium stearate content and 0.2% stabilizer content stood in dichloromethane for 18 hours at room temperature. After the dichloromethane was distilled off on a rotary evaporator, a powder was obtained, which was further homogenized in a Brabender plastograph mixing chamber at 200 ° C for 5 minutes.

Films of a thickness of 0.18 mm at 190 ° C and a pressing time of 30 seconds were pressed from the mixture. The control film was prepared in the same manner, except that no stabilizer was added. The foil was irradiated with a mercury vapor lamp RVL-125 W. The uniformity of irradiation was achieved by rotating the samples around the radiation source. The increase in carbonyl groups as a function of the irradiation time is a measure of the degradation of the polymer by UV radiation.

The growth of carbonyl groups was monitored by IR spectrophotometer. The film without the light stabilizer reached ΔΑ _οο = 0.3 after 1400 hours and the film containing the light stabilizer according to formula III reached AAco = 0.3 after 3850 hours.

The subject compound can be incorporated into the stabilized polymer, can be used as a monomer to prepare a homopolyimer, or can be directly used as a low molecular light stabilizer.

Claims (3)

SUBJECT A polymerizable piperidine-type light stabilizer which represents the compound N- (2,2,6,6-tetramethylpiperidyl) -4-methoxycarbonyl-γ-lactam of formula III OF THE INVENTION is fed with 4-amino-2,2,6,6-tetramethylpiperldine of formula II 2. A process for the preparation of a stabilizer of the formula III as claimed in claim 1, characterized in that, for the itaconic acid dimethyl ester of the formula I. CH-C _'from CH-COO-CH 3) in methanol solution for 24 hours at 25 degrees Celsius and 2 hours at reflux temperature.