DE2136085C3 - Molding compounds based on vinyl chloride polymers - Google Patents

Description

a) 50 to 99.95% by weight vinyl chloride,

b) 0.05 to 10% by weight divinylbenzene or Diacrylic or dimethacrylic acid esters of mono-, di-, tri- or tetraethylene glycol as a crosslinker,

c) 0 to 49.95% by weight of at least one ethylenically monounsaturated monomers.

The invention relates to new molding compositions based on vinyl chloride polymers with improved Processability particularly suitable for extrusion, blow molding and vacuum forming are and molded articles with excellent surface properties such as gloss and Transparency as well as superior mechanical properties result.

In general, vinyl chloride polymers have excellent physical and chemical properties, such as toughness, aging resistance, chemical resistance, while processability because of the low plasticity of the material is inadequate for 3s and in particular extrusion, vacuum or blow molding take place under difficult conditions have to. It is therefore difficult to obtain molded articles made of vinyl chloride polymers whose gloss and transparency are excellent.

To remedy these deficiencies, plasticizers or acrylate polymers have hitherto been included in the vinyl chloride polymer built-in. However, the incorporation of plasticizers leads to molded articles with reduced Hardness and a lower softening point, while the incorporation of acrylate polymers cause defects in terms of transparency, since the acrylate polymer with vinyl chloride polymer less is compatible or difficult to disperse in them.

It has now been found that the incorporation of 0.1 to 20 wt .-% by copolymerization of vinyl chloride crosslinked vinyl chloride copolymers obtained with at least one polyfunctional monomer in polyvinyl chloride leads to usable molding compounds which are free from the aforementioned defects, d. H. in particular, have improved processability and from which molded articles with excellent Surface properties such as gloss and transparency as well as improved mechanical properties are available.

More specifically, the molding compositions according to the invention are based on vinyl chloride polymers out

A. 80 to 99.9 wt% polyvinyl chloride, 6s

B. 0.1 to 20 wt .-% of a crosslinked vinyl chloride copolymer produced by emulsion copolymerization out:

a> 50 to 99.95% by weight vinyl chloride,

b) 0.05 to 10 wt .-% divinylbenzene or diacrylic or dimethyl acrylate of Mono-, di-, tri- or tetraethylene glycol as crosslinker,

c) 0 to 49.95% by weight of at least one ethylenically monounsaturated monomer.

The crosslinked vinyl chloride copolymer to be introduced into the polyvinyl chloride or to be mixed with it is made using polyfunctional monomers, namely diviiylbenzene or diacrylic or dimethacrylic esters of Obtain mono-, di-, tri- or tetraethylene glycol. Examples of ethylenically unsaturated monomers for The crosslinked vinyl chloride copolymer is produced using olefins such as ethylene, propylene and halogenated Olefins such as dichloroethylene, vinyl esters such as vinyl acetate and esters of acrylic acid and methacrylic acid.

The crosslinked vinyl chloride copolymer is produced so that it is in finely divided form or as Powder is obtained, since it is then better dispersible in the polyvinyl chloride and the molding compound obtained is easier to process; emulsion polymerizations in an aqueous medium are used for this purpose. The Cross-linked vinyl chloride copolymers produced by emulsion polymerization lead to molding compounds, from which molded articles with improved uniformity and better surface properties can be obtained are.

A preferred mode of emulsion polymerization is carried out as follows: Deionized water, a Emulsifier and a pH regulator are placed in an autoclave. After passing through it becomes the mixture of nitrogen vinyl chloride and a copolymerizable polyfunctional monomer and after If desired, a copolymerizable ethylenically unsaturated monomer added. The mixture is heated to the predetermined polymerization temperature and then to initiate the polymerization mixed with a catalyst dissolved in a small amount of water. The for copolymerization too using emulsifiers are not critical; H. they can be among nonionic and anionic surfactants can be appropriately selected, however, anionic surfactants become Agents such as, in particular, sodium alkyl sulfosuccinate, potassium salts of higher fatty acids such as stearic acid or oleic acid preferred. These emulsifiers lead to copolymers with a particularly low color. A copolymer latex produced in this way is coagulated by adding an inorganic salt, the copolymer recovered by filtration, washed with water and then dried to a powder.

The polyvinyl chloride to be considered as the main component of the present composition can be prepared by conventional polymerization processes.

Obviously, the particular way in which the crosslinked vinyl chloride copolymer is incorporated into the Polyvinyl chloride is introduced or incorporated, likewise not critical. So can the crosslinked vinyl chloride copolymer for example with the polyvinyl chloride simply in a dry state with the help of a conventional mixer such as a "Henschel mixer" physically mixed.

Small amounts of additives such as stabilizers, dyes, plasticizers and fillers can also be used can be incorporated into the composition of the invention as desired.

When practicing the invention, at least 0.1 percent by weight (based on the weight of the composition) cross-linked vinyl

in "parts" and "percent" are based on weight.

example 1

A. Manufacture of a
crosslinked vinyl chloride copolymers

das uewicni uci i.usaimucusciz.ungj verneizies vinyl- 370 parts were deionized in an autoclave

chloride copolymer in the resulting joint- water, 1 part disodium hydrogen phosphate and 1 part

should be present so that the merits of invention sodium sulfosuccinate are given. About this mixture

At least to a small extent, 100 parts were produced after nitrogen was blown through

to step. The incorporation of a large amount, i.e. via vinyl chloride and 1 part of ethylene glycol dimethacrylate

20% of crosslinked copolymers leads m together (hereinafter referred to briefly with EDMA) hinzu-

Compositions with deteriorated surface properties and the mixture is heated up. After reaching

stocks. The total amount of crosslinked vinyl at a temperature of 50 ° C was 0.5 parts of water

chloride copolymers in the composition lie! 15 peroxide in 30 parts of deionized water for

therefore preferably within a range from initiation of the polymerization to the mixture.

01 to 20 percent by weight given. The polymerization was conducted at a tempera- 'In general, the crosslinking results Eires linear temperature of 50 ⁰ C over a period of 2 hours.

Polymers increased tensile strength, but after which the conversion reached 90%, and it became reduced elongation. It should be noted, however, by heating it up for another 2 hours under 20 that the vinyl chloride polymer of the invention completes stirring. The polymer composition thus produced with the abovementioned crosslinked 0.1% strength aqueous aluminum chloride-containing vinyl chloride copolymers incorporated (in the specified amount of latex in 1000 parts of a ratio for coagulation) an increased stretch and sen. The coagulated polymer was then thinned increased Young's modulus in addition to increased tensile strength. The polymer was absent owns. In particular, the stretch is in the high waist, washed with water and then to one temperature range above the transition temperature Powder dried (hereinafter referred to as Resin I

2 order of polyvinyl chloride is drawn about 1.3 to 2 times), higher than the original stretch. So if the
composition according to the invention, for example 30

Is formed into a sheet or sheet in an extruder with a T-die, breaks or tears and uneven thickness was not observed, and the resulting film was excellent in gloss and transparency.

Furthermore, the resulting sheet material can be polymeric as compared to one made of only vinyl chloride material produced without the addition of crosslinked vinyl chloride copolymer, a vacuum forming

35

B. Making a
Vinyl chloride polymer composition

100 parts of polyvinyl chloride having a degree of polymerization 720 and 2 parts of tin stearate stabilizer were carefully placed in a "Henschel mixer" mixed and then to achieve a vinyl chloride polymer composition with the various amounts of crosslinked indicated in Table I Vinyl chloride copolymers (resin I) added.

rem produced material, a vaKuunuormgeoung The composition was made with an extruder

within a further temperature range below ₄ o with a diameter of 40 mm around a vacuum. thrown and sheeted into articles of greater depth at a resin temperature of 185 ° C and it also results in less surface material being extruded. The resulting orbit rate; ; ai cracks or fissures which are often observed in the conventional form compared to one made of polyvinyl chloride. The combination without the addition of cross-linked vinyl chloride copolymers also has remarkable properties- 45 (Harzl) material is excellent in other molding processes and is, - surface smoothness and gloss as well as better, for example, more favorable through blow molding and uniformity in terms of thickness, · the Hann - Carbon black processed, the composition being materials. ■, ■ a ■ a

shows a higher flowability. The properties of the Bahnmater.a s.nd in the

Since both polymer components vinyl 50 following Table 1 together gelalit. If they contain chloride as the sole or main component, they are better dispersible and compatible with one another. The molded articles produced therefrom are therefore of excellent uniformity and excellent surface gloss and 55
Transparency with little or no "fish eyes".
The surface properties are almost the same
superior to or superior to those of molded articles made of vinyl chloride polymers without the addition of crosslinked vinyl chloride copolymer. ^

From the above explanation it follows that the The composition of the invention by a suitable molding process such as injection molding. Extrusion. Blow molding, vacuum molding into an object of any desired shape t> s can be shaped.

The invention is further explained below using Reknielen, in which all information

table

Added

amounts

of resin 1

veil

11.4

10.3

9.6

8.8

9.2

9.0

10.4

9.9

11.5

ZugfeMigkeil
ikg cnrl

52.0
52.5
53.1
53.3
56.4
60.9
54.8
62.3
62.0

strain

l ° o)

331.5 406.X 464.4 497.9 552.4 551.9 566.7 568.2 570.4

The haze was determined in accordance with Japanese Industrial Standard JIS K 6714 on a thin sample plate made from the above sheet material by press molding at a temperature of 195 ° C. The tensile strength (in kg / cm ²⁾ and elongation (elongation percentage at break,%) was prepared according to the Japanese Industrial Standard JIS K 6301 at a thinner from the above plate H = 3 hanteliörmigen sample under the following test conditions determined: temperature 90 ⁰ C, load 100kg, initial distance between the clamps or clamping points 30 mm, speed at which the clamps are removed (from one another): 200 mm / min.

As Table I shows, compared to a sample made from polyvinyl chloride without the addition of the crosslinked vinyl chloride copolymer (Resin I), the thin plate has practically the same or less haze (which is closely related to the better transparency / sheet material above), and Tensile strength and elongation are increased by about 1.3 to 1.7 times. With regard to the expansion, the installation of networked! Vinyl chloride copolymer thin in an amount of about 3% is sufficient for practical use.

For comparison purposes, the above examples (available commercially for mixing with polyvinyl chloride, [ "] = 2.07 in CHCl ₃ at 25 ° C; ZusammenbCtzung: methyl methacrylate / ethyl acrylate = 90/10) with a Acry lat polymers repeated, the was used in place of the resin I under otherwise practically identical conditions.

The results obtained are summarized in Table 2.

Table 2

35

40

45

The web material produced with the addition of acrylate polymers shows in comparison to polyvinyl chloride only a higher tensile strength and elongation at higher temperature, but it is that with installation material made of resin I in the overall properties and in particular in terms of transparency and inferior to the surface gloss. Further, the shows one by compression molding from the sheet material produced thin plate certain veils a noticeable increase when the built Amount of acrylate polymers exceeds 10%, while the thin plate made according to the invention compared to polyvinyl chloride without the addition of Resin 1. exhibits equal or less haze.

Example 2

The process according to Example 1 was repeated, except that the amounts of EI) MA used were changed at 6s of the preparation of the crosslinked vinyl chloride copolymer and 5 parts of copolymer were added to 100 parts of polyvinyl chloride under otherwise practically constant conditions for the preparation of the web material. The properties of the sheet material are summarized in Table 3.

Table 3

Added veil tensile strenght strain crowd
of acrylic Polymers 1%) (kg / cm ² ) (% l (%) 11.8 54.2 500.8 1 11.2 53.6 512.3 3 12.4 55.8 540.0 5 24.5 56.8 539.1 10 30.6 57.2 548.7 20th

Used veil tensile strenght strain crowd to EDMA (%) (kg / cnr) (%) (%) 7.7 58.7 498.7 0.1 9.0 57.1 523.3 0.5 9.0 60.9 551.9 1 8.9 60.4 554.9 2 9.7 60.8 560.1 3 10.2 59.3 559.3 5

As a reference for comparison of the crosslinked structure of the Anquellungsgrad was determined as follows: Films of a thickness of 0.2 mm were produced from the cross-linked vinyl chloride copolymer at a temperature of '85 C ³ by press molding. After leaving OJ g of the film sample in 50 ml of tetrahydrofuran at a temperature of 30 ° C. for 48 hours and filtering the sample through a 100 "mesh" wire screen (0.15 mm mesh size), the weight of the swollen sample (as W ₁ referred to) and then the weight of the absolutely dry sample (referred to as W ₂ ) measured and the degree of swelling calculated according to the following equation:

Degree of swelling = (W ₁ - W ₂ ) / W ₂

The one measured on the resulting sheet materials The degree of swelling is shown in Table 4.

Table 4

Amounts of EDM A used Swelling gray 0.1 13.3 0.5 11.4 1 9.9 2 10.1 3 9.5 5 9.3

It has been observed that the degree of swelling decreases with increasing amount of EDMA, the fog increases slightly and the elongation also increases, but this is "intercepted" when the used EDMA amount exceeds 3%, i.e. H. the degree of swelling then falls below 9.5. Interpret these appearances indicates that the copolymer used in the present invention has a sufficiently crosslinked structure door has the purpose intended by the present invention.

Example 3

The procedures of example! I have been repeated however, divinylbenzene (hereinafter abbreviated as DVB). Di-. Tri- and Tetraäthylcngiykoldimethacrylate (abbreviated as Di-, Tri- and Tetra-EDMA) separately in place of EDMA as polyfunctional Monomers in quantities of 2% for the production of cross-linked! Vinyl chloride copolymers used

and 5 parts of the above copolymer in 100 parts of polyvinyl chloride with otherwise practically the same Conditions have been incorporated.

The properties of the resulting sheet materials are shown in Table 5. This becomes It is clear that all sheet materials of this example - compared with the one made of polyvinyl chloride without Addition of crosslinked vinyl chloride copolymer made material - higher tensile strength and Own stretch.

Table 5

Polyfunctional
Monomer veil
(%) train
strength
(kg / crn ^ strain
t%) DVB
Di-EDMA
Tri-EDMA
Tetra EDMA 10.4
9.6
10.1
9.5 58.2
61.3
61.0
59.4 538.4
549.0
552.1
543.8

Example 4

250 parts of deionized water and 0.3 part of polyvinyl alcohol (average degree of polymerization of 2000) were placed in an autoclave. After lived through nitrogen through the mixture further 100 parts of vinyl chloride were contacted with dissolved therein 0.6 part of lauroyl peroxide and 10 parts of EDMA in the autoclave and the mixture was then subjected to 15 hours with stirring to a suspension polymerization at 50 ⁰ C. The resulting granular polymer was filtered off, washed with water, dried and then mixed with polyvinyl chloride and formed into a sheet in a manner similar to Example 1. . .

Properties of the thin, made from the tape material Plate manufactured by compression molding are in l abelle 6 specified. From this it can be seen that the produced plate has less haze and higher tensile strength and elongation than a Material made from polyvinyl chloride without the addition of crosslinked vinyl chloride copolymers.

Table 6

crosslinked vinyl chloride copolymer were excellent in transparency and Surface gloss, less distortion on weld parts and an attractive appearance.

Example 6

All of the sheet materials mentioned in Example 1 became thin plates each having a thickness 1.3 mm pressed, from which cylindrical troughs with a diameter of 100 mm and a depth of 50 mm were made by vacuum forming. The web material according to the invention had compared with that made from polyvinyl chloride without the addition of crosslinked vinyl chloride copolymers Material, a greater latitude in terms of the temperature range in which the vacuum forming could be made, and the molded articles produced showed excellent Shine.

Furthermore, using various shapes with a diameter of 100 mm and different Deep vacuum forming test was performed.

The molding properties are shown in Table 7.

given, in which as "adaptation temperature". "Foam temperature" and "shape depth" are the minimum • The minimum temperature at which the test sample adapts well to the shape of the mold Temperature at which the test sample will foam

begins and specifies the maximum depth of a shape at which no »pinhole cracks« have yet been created are.

Table 7

40

45

Added veil tensile strenght Amounts of networked em
Vmyl chloride (%) (kg / cm ² ) polymers 8.8 54.8 r%) 9Y 53.3 3 9.8 59.4 5 10

strain

1%) added

Amounts of

networked

Vinvlchlond-

copolymers

J% I

0.1
0.5
1.0
3 5 10

Vacuum mold temperature

Adaptation temperature
I Ct

78 79 SO 80 82
Sl
83

Foam-

temperature

I C)

Form depth c

Immt

151 159 166 172 175 181 184

70

80

80

100

100

100

100

512.2 541.4 553.8

⁵⁵ A polyvinyl chloride web material without cross-linked λγ Lhioridoolvmeres proves to be a problem with a shape of less than 70 mm with respect to the equal Dk * e of the resulting article according to the invention shows web material

Example 5

Ml onem inner or outer diameter of M ™ "· B min were from all Vinylchloridpolymerzusammenseuungra at a temperature of 195 ° C tubes made from which cylindrical" having a diameter of 50 mm and - "of 180 mm produced by blow-molding in one were . the resulting bottles show compared DTD ^ rfindungsgemäße cooperation with those consisting of polyvinyl chloride without tensile strength and elongation. _Ht n _U ng of vakuumgeform-

can.

Claims (1)

2i 36085 τ / Claim: Molding compounds based on vinyl chloride polymers, consisting of A. 80 to 99.9 wt% polyvinyl chloride, B. 0.1 to 20% by weight of an emulsion copolymerization produced cross-linked vinyl chloride mixed polymer from: