DE1295184B - Stabilization of polyolefins and mixtures of polyolefins and basic nitrogen condensates - Google Patents

Description

It is known that products based on polyolefins are exposed to heat during processing degraded in a certain way, especially in the presence of atmospheric oxygen. Farther it is known that manufactured goods based on crystalline polyolefins protect against exposure to light and are sensitive to heat. This degrading effect can be achieved through the addition of special protective substances to the polymer, especially during the manufacture of fibers, Films and the like.

In general, small amounts of amines, phenolic compounds, aminophenols, Phosphites, thiophosphites, chelates of the subject of the invention is a stabilizing Mix of

a) an aliphatic thioester, preferably obtained by esterification of / ?, ß-thiodipropionic acid with long-chain aliphatic alcohols or by esterification of thiodiglycol with long chain aliphatic acids;

b) a polyvalent phenol which optionally contains sulfur, preferably 4,4'-thio-bis-6-tert-butyl-3-methylphenol;

c) a nickel phenolate of a bis-p-alkylphenol monosulfide and

d) if necessary a metal soap,

which shows a very high stabilizing effect when

Transition metals (Ni), organotin compounds, 15 they in proportions of 5% or less with crystalline Triazole compounds, carbamates and thiocarb olefin polymers are mixed into fibers with amates, oximes, polyquinolines and the like. particular stability

In Italian patents 613 737 and 609 246 of Ferro Chemical Corp. and in the U.S. Patent 3,006,886 to Hercules Co. is the stabilization of polyolefins and others Polymers with nickel phenates of bis-p-alkylphenol monosulfides with the likely structure

(D

special stability against the effects of heat and light as well as against aging can be.

The stabilizing mixtures according to the invention are used to stabilize crystalline polyolefins, in particular of polypropylene consisting essentially of isotactic macromolecules as well as compositions based on crystalline polyolefins and basic nitrogen polycondensates, the fibers with improved dyeability are effective against the effects of heat and light as well as against aging.

They are also suitable for stabilizing compositions essentially on the basis of crystalline polyolefins, which by adding organic or inorganic color pigments for Polymer stabilizer mixture were dyed prior to spinning.

In general, the stabilizer mixture is added to the polymer in proportions between 0.02 and 5 percent by weight added.

The mixture can be used together with pigments, dyes and fillers.

As aliphatic thioesters, which are particularly suitable components of the mixture, the following may be mentioned:

a) thioesters of thiodiethylene glycol, such as didodecoyl thiodiglycolate, Octadecoyl thiodiglycolate and the like, or

b) the thioesters of ^, jS'-thiodipropionic acid, such as Lauryl thiodipropionate.

Particularly suitable polyhydric phenols are, for example, 4,4'-thio-bis-6-tert-butyl methacresol and polyphenols (obtained by condensation of aldehydes and ketones with alkylphenols) of the general Formula I or II

35

40

45

OH

(2)

55 HO

OH (I)

60

described.

In addition, US Pat. No. 3,006,885 to Hercules Co. describes the stabilization of polypropylene with a synergistic mixture of a nickel phenolate of bis-p-alkylphenol monosulfide with chromans or with alkylidene-bis-alkylphenols .

(Π)

in which R is hydrogen or an alkyl radical (and at least one radical R in each ring is an alkyl radical

is) and R ¹ and R ^{2 are} hydrogen or an alkyl radical. These compounds are described in Italian patents 606 804, 615 441 and 623 440 and in British patent 571 943; ortho-hindered and para-substituted phenols, trishydroxyarylpropanes (described in Italian patent 632 726) and the like.

Among the particularly suitable nickel phenolates of the alkylphenol monosulfides, the following may be mentioned: Nickel phenolates of bis-2-tert-butylphenol monosulfide, des 0,0 '- bis (p - octylphenol) - monosulphide and des O, O'-bis (p-amylphenol) monosulfide.

The stabilizer mixture contains 20 to 80% nickel phenolate and thioester.

Suitable metal soaps are, for. B. calcium stearate, zinc stearate, aluminum stearate, calcium laurate, zinc laurate and aluminum laurate.

The addition of the stabilizing mixture according to the invention to the polyolefin is generally carried out by simple mixing of the stabilizer mixture in the form of powders with the polyolefins Movement carried out.

However, the stabilizers can be added by other methods such as mixing the polyolefins with a solution of the stabilizers in a suitable solvent and then Evaporation of the solvent or by adding the stabilizers to the polyolefins at the end the polymerization.

Furthermore, the stabilizing effect can be achieved by adding the stabilizing mixture applies to the objects, e.g. B. by immersing the latter in a stabilizer solution or dispersion and subsequent evaporation of the solvent.

The stabilizers used according to the invention show good compatibility with polyolefins Melt condition and do not cause staining.

The compositions of stabilizer and polymers are granulated and then in a melt spinning device, preferably as described in the inventor's Italian patent specification 614 043 and preferably using spinnerets of the type described in the Italian patent 600 248 of the inventor and which have a length to diameter ratio of more than 1, spun.

The granulation and spinning is carried out in the absence of oxygen, preferably in an inert gas atmosphere (Nitrogen) carried out.

During the mixing of the polyolefins with the stabilizers according to the invention, optical Fillers and organic or inorganic color pigments are added.

The threads produced from the stabilized polymers are, after spinning, a stretching treatment with stretching ratios between 1: 2 and 1:10 at temperatures between 80 and 150 ^° C. in stretching devices that are heated with hot air, steam or the like or by means of a heating plate, subject.

The fibers can then undergo dimensional stabilization treatment under free or restrained shrinkage conditions at 80 to 160 ° C, as in Italian patents 566 914 and 588 318 described by the inventor.

Compositions stabilized according to the invention are particularly suitable for the production of individual and multiple threads, fiber strands or staple fibers, voluminous yarns as well as other molded goods, like foils.

The invention is illustrated in the following examples.

The polyphenol obtained by reacting nonylphenol with formaldehyde has the formula

OH

(CH ₂ ) ₈ -CH ₃ (CH ₂ J ₈ -CH ₃

3 4th example 6th 7th 8th 2 5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 - - - 0.2 - - - 0.2 - - - 0.2 - - - 0.2 0.2 - - - 0.2 - - - 0.5 0.5 0.2 0.5 0.5 0.3 0.3 0.5 0.3 0.3 0.3 0.3 0.25 0.25 0.3 0.25 0.25 0.25 0.25 0.25

Polypropylene:
Intrinsic viscosity [»/] = 1.60
Ash content = 0.029%
Residue after heptane extraction = 94.4%

Didodecoylthiodiglycolate,% · ■

Lauryl thiodipropionate,%

4,4'-thio-bis-6-tert-butyl methacresol,%

Polyphenol (from CH ₂ O and
Nonylphenol)%

Tris-hydroxy-3-methyl-6-tert-butyl-phenylpropane, %

Nickel phenolate of bis-p-tert-butylphenol monosulphide, ° / ₀ .

Calcium stearate,%

TiO ₂ ,%

Making the Mix

Spinning Conditions:
Screw ^{temperature, 0} C ...

Head temperature, ⁰ C

Spinneret temperature, ⁰ C ..

0.5

0.2

0.5 0.3 0.25

in a Henschel mixer

250 250 250

250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250

250
250
250

continuation

Example 3 4 5

Spinning Conditions:

Spinneret type

Maximum pressure, kg / cm *

Winding speed,
m / min

Stretching conditions:

Temperature, ⁰ C

medium

Stretch ratio

Properties of the stretched
Fibers:

Tensile strength, g / den

Strain, %

Thermal degradation (percent
remaining intrinsic viscosity [rß
after spinning)

Stability towards
accelerated thermal
Aging (percent residual tensile strength after 200 hours at 120 ° C in a heating cabinet with air circulation)

Stability to sunlight (percent residual tensile strength after 300 hours of exposure to summer sunlight [actual exposure] until the 7th shade changes in the
Standard blue scale)

60 / 0.8.16 67

390

130

Steam 1: 5

5.88 22

72

82

60 / 0.8.16
65

390

130

steam
1: 5

5.6
25th

78

84

60 / 0.8.16 71

390

130

Steam 1: 5

5.2 27

60 / 0.8.16 62

390

130

Steam 1: 5

60 / 0.8.16
75

390

130

steam
1: 5

5.75
22.5

75

77

60 / 0.8.16
78

390

130

steam
1: 5

5.81
24

72

75

60 / 0.8.16
63

390

130

steam
1: 5

5.5
25th

78

15th

60 / 0.8.16
74

390

130

steam
1: 5

5.1

27

75

brittle

60

87

continuation

61

65

50

53

60 / 0.8.16 71

390

130

Steam 1: 5

11 12th 13th example 15th 16 17th 10 0.5 14th 0.5 0.5 - - - - 0.5 - - - 0.5 0.2 - - - 0.2 0.2 - - - · - 0.2 - - 0.2 - - - - 0.2 0.3 0.3 0.3 - 0.3 0.3 0.3 0.3 0.25 0.25 0.25 0.3 0.25 0.25 0.25 0.25 0.25

Polypropylene:

Intrinsic viscosity [jj] = 1.60

Ash content = 0.029%

Residue after the heptane

extraction = 94.4%
Didodecoylthiodiglycolate,% ...

Lauryl thiodipropionate,%

4,4'-thio-bis-6-tert.butylmetha-

cresol,%

Polyphenol (from CH ₂ O and

Nonylphenol)%

Tris-hydroxy-3-methyl-6-tert.-

butylphenylpropane,%

Bis-p-tert.- nickel phenolate

butylphenol monosulfide,% ...

Calcium stearate,%.

TiO ₂ ,%

Making the Mix

Spinning Conditions:

Screw temperature ^{, 0 C}

Head temperature, ⁰ C

Spinneret temperature, ° C ...

Spinneret type

Maximum pressure, kg / cm ²

Winding speed,
m / min

Stretching conditions:

Temperature, ⁰ C

medium

Stretch ratio

in a Henschel mixer

250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 250 60 / 0.8.16 60 / 0.8.16 60 / 0.8.16 60 / 0.8.16 60 / 0.8.16 60 / 0.8.16 60 / 0.8.16 60 / 0.8.16 68 73 64 67 78 73 65 69 390 390 390 390 390 390 390 390 130 130 130 130 130 130 130 130 steam steam steam steam steam steam steam steam 1: 5 * 1: 5 1: 5 1: 5 1: 5 1: 5 1: 5 1: 5

250 250 250

60 / 0.8.16 73

390

130

Steam 1: 5

continuation

10 11 12th 13th example
14th 15th 16 17th 18th Properties of the stretched
Fibers:
Tensile strength, g / den 5.55 5.28
28.2
77
brittle
55 5.5
25th
74
25th 5.7
23
85
brittle 5.5
25th
88
brittle 5.6
21
64
brittle 6.1
20.5
75
brittle 5.9
21
81
brittle 5.5
24.5
71.5
brittle
86 Strain, "/"
Thermal degradation (percent
remaining intrinsic viscosity [//] according to
Spinning)
Stability towards
accelerated thermal
Aging (percent residual tension
strength after 200 hours
120 'C in a heating cabinet with
Air circulation)
Stability to sunlight
(Percent residual tensile strength according to
300 hours of exposure [did
neuter exposure] to
Change of the 7th shade in
the standard blue scale 23
76
IK
54

Claims (1)

Claim: Use of mixtures of a) aliphatic thioesters, b) polyhydric phenols, which may contain sulfur, c) Nickel phenolates of alkylphenol monosulfides and d) optionally metal soaps to stabilize polyolefins, mixtures of polyolefins and basic nitrogen condensates as well as by melt spinning polyolefins or mixtures of polyolefins and basic nitrogen condensates produced fibers against the effects of heat and light as well against aging. 909 520/565