CS272622B1 - Agent with increased hydrolysis resistance for polymers stabilization - Google Patents

Abstract

The invention concerns a preparation with increased resistance to hydrolysis for stabilisation of polymers, consisting of 3,9-bis(alkaralkylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro(5,5)undecane as an active substance and tertiary amine in a quantity of 0.1 to 5.0 % by weight as an inhibitor of the hydrolysis of the active substance. The invention can be used in the chemical industry.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition with increased resistance to hydrolysis for the stabilization of polymers, consisting of 3,9-bis (alkaralkylphenoxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [5,5] undecane as active ingredient and an inhibitor of its hydrolysis.

The increasing demand for protection of polymeric materials and substrates against thermo-oxidative degradation during their processing, storage and exploitation is currently ensured by several types of stabilizers. One of the most important classes of effective stabilizers for synthetic polymers are organic phosphites, which have been the focus of most recently cyclic phosphites based on pentaerythritol, of which derivatives containing more than 14 carbon atoms are solids under normal conditions, while which low-molecular types are liquids. These compounds are particularly suitable for the stabilization of polyolefins, vinyl polymers, polystyrenes, polycarbonates, rubbers, oils, and the like. Their common disadvantage is the tendency to absorb air humidity during storage, transport and handling, which leads to their hydrolysis and thus to a reduction in their stabilizing efficiency. Said undesirable processes are more pronounced with solid derivatives having a substantial larger surface area per unit mass and consequently absorb more atmospheric moisture, leading not only to a more pronounced hydrolysis and a decrease in the stabilization efficiency, but also to undesirable changes in physico-chemical properties, the bulk material lumps and, depending on the amount of absorbed water, passes through the plastic state into a liquid state, thereby degrading. The basic criterion for changing the quality of a solid phosphite is a decrease in its melting point. It is clear from the above that the problem of hydrolytic stability of solid phosphites is much more severe than that of liquid phosphites.

Several methods of protecting, in particular, liquid organic phosphites against hydrolysis by atmospheric moisture are known in practice and in the literature. One of these is to protect the product against atmospheric moisture by storing, transporting and processing it in a dry atmosphere, resp. in an inert gas atmosphere. However, it is costly and not always sufficiently effective to protect. A more efficient way of stabilizing phosphites against hydrolysis is by adding a suitable additive capable of inhibiting the absorption of air humidity. It is known from industrial practice to stabilize low molecular weight liquid phosphites by the addition of magnesium oxide or related substances, which however, during storage, fall out in the form of a deposit and thus cease to function. Low molecular weight liquid phosphites can also be stabilized against the effects of moisture with some nitrogen compounds (US 3,553,298, US 3,703,496). JP 52 225 (1977) describes the stabilization of organic triphosphites by the addition of metal carboxylates, whereas JP 51 37136 (1976) describes combinations of solid organic phosphites with a low molecular weight polyolefin or a higher ketone and in JP 54 097 588 (1979) with esters derived from tetrametylpiperidinolu. There is no known method of increasing the hydrolysis resistance of 3,9-bis (alkaralkylphenoxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [5,5] undecanes, which represent virtually the latest high-performance solids group phosphite stabilizers for polymers (CS 245 205).

We have now found a composition with increased resistance to hydrolysis for polymer stabilization, consisting of 3,9-bis (alkaralkylphenoxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [5,5] undecane of formula I

wherein R is a linear or branched C, to C _g alkyl group, R ^C is a _C? to _Cg aralkyl, X is an integer of 0,1 or 2 and y is an integer of 1 or 2 as the active ingredient and the active agent an inhibitor of the hydrolysis stage of the invention. The subject matter of the invention is that the composition comprises

CS 272 622 B1 as a tertiary amine hydrolysis inhibitor in an amount of 0.1 to 5.0 wt. It has also been found to be advantageous if the active ingredient of the composition according to the invention is 3,9-bis / 2-

1-dimethylethyl) -4- (1-methyl-1-phenylethyl) phenoxy [-2,4,8,10-tetraoxa-3,9-diphosphaspiro] 5,57 undecane and the active ingredient hydrolysis inhibitor hexamethylene-tetramine. As the tertiary amine in the function of the active ingredient hydrolysis inhibitor of the composition of the invention, trialkylamine, trialkanolamine or polyalkylpolyamine can be used.

The composition according to the invention is applied to the polymer substrate in an amount of 0.01 to 1.0% by weight, the best results being obtained in a concentration range of 0.05 to 0.5% by weight. to the base polymer substrate, whether applied alone or in combination with other additives such as antioxidants, light stabilizers, pigments, fillers, antistatic agents, flame retardants and the like. It can be added directly to the polymer substrate during its manufacture or during its processing by conventional processing techniques. It can also be applied in the form of polymer concentrates. The polymer substrate stabilized by the composition according to the invention can be processed by extrusion, injection molding, rolling, pressing or other processes to produce products such as fibers, foils, tapes, profiles, thatch, pipes, deposits on suitable substrate material and the like. The polymeric substrate may be polyolefins, polystyrenes, ABS, polyamides, polyvinyl chloride, combinations thereof with other polymers, rubbers, oils or other polymers.

An important advantage of the composition according to the invention over the known solid pentaerythritol-based phosphites and in comparison with the unstabilized active ingredient is the markedly prolonged stability when exposed to atmospheric atmospheric humidity as well as to high relative humidity boundary conditions. Due to the high degree of inhibition of the hydrolysis of the active ingredient, the composition according to the invention retains virtually the original chemical composition and physicochemical properties over a long period of time, and hence good shelf life, handling and processability. It retains the hydrolysis resistance even in the polymer substrate, which thus obtains long-term stability. Said advantages of the composition according to the invention will have a significant positive effect on the economics of its active substance application, since it will significantly reduce its losses due to hydrolysis and prolong the life of the stabilized polymeric materials and substrates, while the amine component additionally adjusts the amount of phosphite accordingly. amount of composition.

The following examples illustrate but do not limit the scope of the invention.

Example 1

B of 3,9-bis (2-methyl-4- (1-phenylethyl) phenoxy) -2,4,8,1O-tetraoxa-3,9-diphosphaspiro [5.57] undecane was mixed with 0.5 wt. of the hydrolysis inhibitor tested, accurately weighed 5 g of the mixture, and the sample was exposed to air at constant temperature relative humidity of 90 + 2% in a closed glass cabinet at room temperature and a sample weight increase due to water absorption was recorded periodically. The percentages found are in Table 1.

Table 1

hydrolysis inhibitor Sample weight increase in% after exposure 2 days 4 days 8 days - 1.5 4.6 20.7 magnesium oxide 1.2 4.1 13.9 triethylamine 0.8 3.3 8.1 triethanolamine 0.7 2.2 7.4

The tertiary amines used significantly reduced the absorption of atmospheric moisture by the sample which, unlike the non-stabilized sample and the magnesium oxide-stabilized sample, retained the original powder form.

CS 272 622 B1

Example 2 ε 3,9-bis / 2- (2-ethylhexyl) -6- (1-phenylethyl) phenoxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro / 5,5 % of undecane was mixed with 1.5 35 wt. of the hydrolysis inhibitor under test and the procedure of Example 1 was followed, the samples being exposed to atmospheric conditions at room temperature. The observed weight gain values of the samples, expressed in weight. percentages are given in Table 2.

Table 2

Inhibitor of hydrolysis Sample weight increase in% after exposure 5 days 10 days 15 days 31 days - 1.5 6.5 12.2 26.3 magnesium oxide 1.05 2.5 4.8 16.7 triisopropanolamine 0.3 0.6 1 5.9 diethylenetetramine 0.08 0.26 1.1 4.7

The tertiary amines used maintained the hydrolytic stability values of the active substance at a substantially higher level than in the case of the unstabilized sample and the magnesium oxide containing sample.

Example 3

100 ε 3,9-bis / N - (t, 1-dimethylethyl) -4- (1-methyl-1-phenylethyl) phenoxy / -2,4,8,10-tetraoxa-3,9-difoafaspiro / 5, 5 / undecane was mixed with the hydrolysis inhibitor under test and proceeded as in Example 1 except that the relative air humidity was 100%, and the content of hydrolyzed 2- (1,1-dimethylethyl) released by hydrolysis was monitored periodically by liquid chromatography. -4- (1-methyl-1-phenylethyl) phenol by weight in the sample. The values are summarized in Table 3 ·

Table 3

Hydrolysis Inhibitor,

Content of released substituted phenol

& wt. (% by weight) after exposure 0 days 2 days 5 days 7 days 0.81 15 46.0 53.0 triethanolamine: 1.0 1.3 6.4 19.0 23.0 4.0 ’, 3 1.6 5.4 7.0, hexamethylene TETRAMINE: 0.15 1.5 2.7 8.9 13.0 0.5 1.5 1.5 4.7 6.5 1.25 1.45 1.45 3.1 4.05 4.75 1.45 1.45 2.6 3.2

The tertiary amines used greatly reduced the formation of free 2- (1,1-dimethylethyl) -4- (1-methyl-1-phenylethyl) phenol as a result of the hydrolysis of the active substance by exposure to atmospheric humidity.

Claims (2)

A PSEDMET OF THE INVENTION Wherein R is a linear or branched C ₁ -C ₁₈ alkyl, R is a C ₁ -C ₁₈ aralkyl, x is an integer of 0.1 or 2, and y is an integer of 1 or 2, both of the active ingredient and of the active ingredient hydrolysis inhibitor, 2. The method according to claim 1, wherein the tertiary amine is present in an amount of 0.1 to 5.0% by weight of the active compound hydrolysis inhibitor. A composition having an increased resistance to hydrolysis for polymer stabilization, consisting of 3,9-bis (alkaralkylphenoxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro undecane of formula I rf CS 272 622 B1 4 2. The composition of clause 1 containing 3,9-bis [2- (1,1-dimethylethyl) -4- (1-methyl-1-phenylethyl) phenoxy] -2,4,8,10-tetraoxa as the active substance -3,9-diphosphaspiro (5,5) undecane, characterized in that it contains hexamethylenetetramine in an amount of 0.1 to 5.0 wt.