JP2603667B2 - Low viscosity, semi-crystalline chlorinated polyethylene resin - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to semi-crystalline chlorinated polyethylene resins that can be processed in conventional equipment without the need for plasticizers and other viscosity reducing processing aids.

Various methods for chlorinating olefin polymers, especially ethylene polymers, are known. This method is usually divided into three types: solution chlorination, suspension chlorination and bulk chlorination. Chlorination in aqueous suspensions or inert liquids is known from U.S. Pat. Nos. 2,592,763 and 3,454,544. Bulk chlorination, or chlorination in the absence of a liquid suspension or solvent, is described in U.S. Pat.Nos. 2,890,213 and 4,4
No. 25,206 and British Patent No. 834,905.

The chlorinated polyethylene materials produced by the three chlorination methods differ significantly in physical properties, even though they start with the same polyethylene resin and have the same chemically combined chlorine content. This is thought to be mainly due to the magnitude of the statistical distribution of chlorine in chlorinated polyethylene macromolecules. British Patent Nos. 843,209 and 950,374 illustrate this phenomenon.

As used herein, "lightly blended" means a compound containing 100 parts chlorinated polyethylene resin, 3 parts epoxidized soybean oil, 2 parts calcium stearate, and 0.5 part stearic acid.

By "compound low temperature brittleness value" is meant that a T-50 sample made from the physical blend described in detail in the "Method of Making Roof Membrane Test Samples" section of the present invention is tested by ASTM D-746.

SUMMARY OF THE INVENTION One embodiment of the present invention provides a chemically combined chlorine content of 20 to 33 weight percent of the polymer, 7.5 to 1 per gram.
A heat of fusion of 6 calories, a temperature of 190 ° C. and a shear rate of 145 s ⁻¹ measured 5,000 to 11,000 poise (500 to 1100 Pa · s) as measured with a capillary rheometer having a capillary size of 0.05 inch × 2 inch (0.13 × 5.08 cm)
s), 100 as measured by ASTM D-412-75.
Semi-crystalline with slightly stabilized tensile stress of 150-750 pounds / inch ² (1.0-5.2 megapascals) at% elongation (hereafter referred to as 100 percent modulus) and compounded low temperature brittleness values below -25 ° C Chlorinated polyethylene resin, this polyethylene resin is 2000-9000 before chlorination
Poise (200-900 Pa · s).

Preferred Embodiments "Polyethylene" is defined as an essentially linear homopolymer of ethylene as well as at least 90 mole percent of ethylene and up to about 10 mole percent of one or more ethylenically unsaturated monomers copolymerizable therewith. Means a linear interpolymer. Suitably, the monomer will contain from about 3 to about 18 carbon atoms, such as propylene, butene-1, pentene-1, 3-methylbutene-1, 4-
Methylpentene-1, hexene-1, octene-1, dodecene-1, octadecene-1, 1,7-octadiene and the like.

The polyethylene resin is suitably prepared under the conditions of Ziegler polymerization in the presence of a transition metal-containing catalyst and at least one cocatalyst or activator. Typical catalysts are taught in U.S. Pat. No. 4,246,383. Other catalysts and methods may be used provided that they meet the criteria set forth below.

The polyethylene resin used here meets two criteria. First, the resin has a density of from about 0.94 to about 0.97 g / cm ^3. Second, the resin is about 2000-9000 poise (200
900900 Pa · s).

Advantageously, the polyethylene resin is chlorinated by the suspension or slurry method disclosed in US Pat. No. 3,454,544.

In a typical slurry chlorination process, a suitable time interval,
For example, the polyethylene resin is first chlorinated to a chlorine content of 2 to 10 percent while heating to a temperature of about 90C to about 110C in 10 minutes. The partially chlorinated resin is then further chlorinated on another schedule. In one schedule, chlorination is continued while heating the slurry to a linear temperature for a short period of time, for example, 20 minutes. This linear temperature is chosen to obtain the desired amount of residual crystallinity as reflected by the heat of fusion. Typical linear temperatures are in the range of about 115C to about 123C. "Linear" means a constant and / or isothermal temperature at which the slurry is maintained until chlorination is complete. In the second schedule, there is no linear temperature. The slurry is heated at a constant rate while continuing chlorination until the final temperature and the desired chlorine content are reached. The final and linear temperatures are below the crystalline melting point of the polyethylene starting material. Generally, the final temperature used in the second schedule is
It must be higher than the linear temperature of the first schedule to get the same level of crystallinity. The second schedule is used when a modulus value greater than 100 percent is desired. In general, increasing the amount of chlorine added at linear temperature will conversely decrease the 100 percent modulus.
Temperatures and times are easily determined without experimentation.

Solution methods typically provide amorphous chlorinated polyethylene resins when the chlorine content is from about 25 to about 29 weight percent of the polymer. The fluidized bed (mass) method is suitable for the purposes of the present invention, but has the same chlorine content but a higher 100% modulus value than the resin produced by the suspension method,
This produces chlorinated polyethylene resins with poor stability. Thus, the suspension chlorination method is preferred over any other method.

The chlorinated polyethylene resin of the present invention has certain properties. Its properties include chlorine content, heat of fusion, lightly compounded 100 percent modulus and compounded low temperature brittleness values.

The chlorinated polyethylene resin of the present invention suitably comprises about 20 to about 33 of the polymer, advantageously about 23 to about 30, preferably about 24
It has a chemically combined chlorine content of about 26 percent by weight. It has been found that compounded low temperature brittleness values of less than about -25 ° C, such as -30 ° C, are obtained when the chemically combined chlorine content is less than about 22 percent or greater than about 33 percent by weight of the chlorinated polyethylene.

The chlorinated polyethylene resin has a heat of fusion of from about 7.5 to about 16, preferably from about 8 to about 14 calories per gram as measured by a differential scanning calorimeter. It has been found that increasing the heat of fusion at a fixed chlorine content also reduces the low temperature brittleness value of the formulation, for example, at temperatures above about -25 ° C. Therefore, care must be taken to avoid extremely high heats of fusion. Heat of fusion less than about 7.5 calories / g should also be avoided, as reduced heat of fusion also reduces 100% modulus.

This chlorinated polyethylene resin is about 5,000 to about 11,000,
Desirably, it has a melt viscosity of about 5,500 to about 10,000 poise. In Pascal seconds, this viscosity is from about 500 to about 1100, desirably from about 550 to about 1000. At viscosities less than 500 Pa · s, the blended low temperature brittleness value rises above -25 ° C. 1100Pa
At viscosities above s, this resin is very difficult to process in conventional extrusion or calendering equipment used in roofing material manufacture and conventional extrusion equipment used in the manufacture of cable jackets.

This chlorinated polyethylene resin costs about 150 to about 750 pounds
/ inch ² (1.0-5.2 megapascal), preferably about 350-
It has a lightly formulated 100 percent modulus of about 650 pounds / inch ² (2.4-4.5 megapascals).

The chlorinated polyethylene resins of the present invention may be used in the manufacture of various products, such as polymer-based membranes, wires and cable jackets. This film has the advantage of thermoplasticity,
For example, when vulcanized by radiation curing, it is thermosetting. The thermoplastic film is suitably 1.5 pounds / inch (26.9
Less than 8 kg / m), preferably 1.0 lb / inch (17.8 kg / m)
It has the following membrane blocking values:

The chlorinated polyethylene resin of the present invention may be blended with other components such as fillers, pigments, stabilizers, processing aids, and the like. The amount and type of "other ingredients" will depend on factors such as the effect on the properties of the composition and cost.

Fillers which may be used with the resin of the present invention are natural or synthetic finely divided inorganic materials in the form of regular or irregular particles, flat plates or fiber flakes. Suitable materials include various types and grades of calcium carbonate (whiting), calcium sulfate, mica, talc, kaolin and other clay minerals, silicates, silica, barite, magnesium oxide, magnesium carbonate, aluminum trihydrate, and the like. It includes mixtures of such fillers. Suitably the filler is fine enough to pass through a 100 mesh sieve (US standard sieve). Advantageously, the filler has a spherical diameter of less than about 15 μm.

The filler is suitably present in an amount of from about 10 to about 80 parts per 100 parts by weight of the chlorinated polyethylene resin, whether or not used in making roof membranes or wires and cables. This filler is made of chlorinated polyethylene resin.
Desirably, it is present in an amount of about 10 to about 50 parts per 100 parts by weight.

Organic and inorganic pigments that may be used in combination with chlorinated polyethylene resins in roofing membranes or wires and cable jacket compounds include carbon black, titanium dioxide, and the like, and mixtures thereof. Suitably, the pigment is present in an amount of about 2 to about 50 parts per 100 parts of the chlorinated polyethylene resin. Desirably, the amount of pigment is from about 10 to about 40 parts per 100 parts of the chlorinated polyethylene resin.

Stabilizers are commonly used with the chlorinated polyethylene resin of the present invention to protect the resin against thermal degradation such as processing. Stabilizers conventionally used in the preparation of vinyl polymer and copolymer sheet compositions are suitable. Examples include oxides and / or salts of organic complexes, lead, tin, barium, cadmium, magnesium, sodium. Particular examples include dibasic tin phthalate, tin oxide, magnesium oxide, magnesium hydroxide, sodium phosphate, magnesium carbonate, barium cadmium stearate, and the like. Small amounts of such stabilizers are effective. From 2 to 20 parts of stabilizer per 100 parts of chlorinated polyethylene resin is usually suitable.

It is suitable that the compound containing the chlorinated polyethylene resin of the present invention is mixed by a heated two-roll mill, a Banbury type mixer, a compounding extruder, or an equivalent mixing and compounding device.

 The semi-crystalline chlorinated polyethylene resin of the present invention can be used for wire.
-And when used as part of the cable jacket compound,
Conventional semi-crystalline chlorinated polyethylene resin, such as The Do
w Tyrin from Chemical Company Commercially available as 2552
It is appropriate to mix it with a functional one. Improve workability
Satisfactory results in maintaining the physical properties
Ming chlorinated polyethylene resin is used for all chlorine in the compound
Present in an amount of from 0 to about 50 weight percent of the functionalized polyethylene resin
If you get. This amount is the total chlorinated polyethylene content
About 0 to about 40, preferably about 5 to about 30 weight percent of
It is advantageous. This amount corresponds to the chlorinated polyethylene tree of the present invention.
It depends on the desired properties of the fat and the compound. But this
Is easily recognizable.

Commercial and actual wire and cable jacket compounds have an elongation of about 350 percent or more, about 1000 pounds / in
100 greater than ch ² (psi) (6.9 megapascals (mpa))
% Modulus, ultimate tensile strength greater than about 1300 psi (9.0 mpa), and low temperature brittleness value of less than about -25 ° C.

The following examples are illustrative and are not intended to limit the scope of the present invention. All parts and percentages are by weight except where indicated. All water used was deionized water except those shown. Examples of the invention are indicated by numbers, while comparative examples are indicated by letters.

General chlorination method Polyethylene resin about 20 pounds (9.07 kg), trade name T-
Interface commercially available from Thomson Hayward as detN9.5
Activator 25ml, trade name Mistron Vapor Cyprus Indu as
Talc 100 commercially available from strial Minerals Company
g, and an aqueous slurry containing 189 pounds (85.73 kg) of water
The rally was placed in a reactor and heated to 100 ° C. Open reactor
After removing oxygen, cool to about 95 ° C before starting to add gaseous chlorine.
Rejected. In the first stage, the slurry is brought to constant
0.268 lbs / min while heating to about 110 ° C over a minute
Chlorine was added to the reactor at a rate of (0.12 kg / min). First stage
The chemically combined chlorine content at the end of the floor is about 8
It was calculated to be In the second stage, chlorine
Do not add gas at a rate of 0.214 lb / min (0.097 kg / min).
A straight line of about 115 to about 123 ° C for about 23 minutes at a constant speed
Heat the slurry to temperature. At about 115 ° C, talc 1
Add 00 g and water 2 to the slurry. End of the second stage
About 17 percent of the chemically combined chlorine in
there were. The desired chemically combined chlorine content and heat of fusion
Until it is obtained, it will be chlorine gas at linear temperature and same flow rate.
Chlorination. As an example, a linear temperature of about 23 minutes
Chlorination yields about 25 percent chlorine content
Was. The chlorinated resin is then cooled, washed with water, and then
Dried for strike and blending.

Table I is a list of polyethylene resins chlorinated by the above method. Resin A was a powder produced by a slurry method. It is not commercially available. Resins BE were produced by a solution method and have the trade names The
It is commercially available from Dow Chemical Company in pellet form. Therefore, resins B to E can be used as a thermal size reduction system (Thermofine Size Reduction) commercially available from Wedco.
System) (standard SE-12-C mill) before chlorination
Grind to 13 mil (0.33 mm) particle size.

Manufacturing method of roofing material test sample A physical mixture was manufactured from the following components.

a. Chlorinated polyethylene resin 10 produced as described above
0 copies; b. Product name Mark Commercially available from Argus Chemical as 7119
2.5 parts of a possible barium-cadmium-zinc stabilizer; c. Allied Chemical Corpora as 629A wax
-Oxidized polyethylene wax commercially available from -tion 1.
5 parts; d. Stearic acid 0.8 parts e. Trade name Mistron Vapor As Cyprus Industrial Min
10 parts of talc commercially available from eral Company; f. Trade name U1tranox Borg-Warner Chemical C as 626
Pentaerythritol diphos commercially available from ompany
0.7 parts of fit antioxidant; g. Commercially available from Carstab Corporation under the trade name DLTDP
Possible dilauryl thiodipropionate, thioester
0.5 parts antioxidant; h. Trade name Irganox Ciba-Geigy Corporation as 1076
More commercially available alkylated phenol antioxidants 0.5
Department; and i. Trade name TiPure As E.I.du Pont de Nemour & Com
25 parts titanium dioxide commercially available from pany.

This physical mixture was converted to a molten mixture using a two-roll plastic compounding mill. This two roll mill
It had a set roll temperature of 320 ° F (160 ° C). The molten mixture was then processed on the same roll mill for another 5 minutes at the same set temperature. The processed mixture was taken out of a two-roll mill in the form of a smooth heat-plasticized sheet. The sheet had a thickness of 80-90 mils (0.2-0.23 mm).

The sheet was compression molded to form a sample having a thickness of 0.065 inches (0.165 cm). Compression molding was performed by the following continuous method using hydraulic pressure.

a. 350 ° F (177 ° C) temperature and 100 lb / inch ² (70,3
07kg / m ²⁾ is heated at a pressure of 3 minutes;. B were heated for 3 minutes at a pressure 333 pounds / inch ² at the same temperature (234,122kg / m ^2); c.333 pounds / inch ² (234,122kg / m ² ) Cool by circulating water (about 70 ° F or about 21 ° C) through the press for 3 minutes while maintaining the pressure of ² ). Test pieces were cut from this sample for the tests described below.

Preparation of Wire and Cable Forming Test Samples A physical mixture was prepared from the following components.

a.25 percent chemically combined chlorine content, 12,500 po
As nominal melt viscosity and 11 calories / g nominal heat of fusion
Tyrin The Dow Chemical Comp as 2552
Chlorinated polyethylene resin commercially available from any
Quantification (see Table 4); b. Constant amount of one type of chlorinated polyethylene resin (see Table II)
(See Table IV); c. Trade name Dythal The Associated Lead Company as XL
6 parts of commercially available lead phthalate stabilizer; d. 0.8 parts of stearic acid; e.
2 wax; f. Trade name Agerite R.T.Vanderbilt Co. as resin D powder
Polymerized 1,2-diphenyl commercially available from mpany Incorporated
0.5 parts of dro-2,2,4-trimethylquinoline antioxidant; g. Commercially available from Cabot Corporation under the trade name N-330
20 parts of possible carbon black; h. Talc 25 used in the production of roofing test samples
Part; i. Commercially available from Wyrough & Loser under the trade name HA-85
Chlorinated polyethylene containing effective 85% antimony oxide
6 parts of compound; j. Commercially available from Wyrough & Loser as trade name HE-25
Contains 80% decabromodiphenyl oxide
14.7 parts of a chlorinated polyethylene compound; and k. 25 parts of a high density polyethylene resin (see Table I, resin E).

To mix the ingredients shown in the BR-size Banbury mixer, an inverse mixing method was used. "Reverse" means that the resin components (a) and (b) are added last, not first.

Further components were mixed and converted to a molten mixture according to the following schedule. (A) 77 rotations / minute (8 radians /
(B) 3 min at 116 rev / min (12 radians / sec); and 3 min at (c) 155 rev / min (16 radians / sec). When the mixture reached a temperature of about 300 ° F (149 ° C), the molten mixture was removed from the mixer.

The molten mixture is further processed for 3 minutes using a two-roll plastic compounding mill. This two roll mill is 32
It had a set roll temperature of 5 ° F (163 ° C). The processed molten mixture was taken out of a two-roll mill in the form of a smooth heat-plasticized sheet. This sheet is about 200
It had a thickness of mill (5.1 mm).

Return 600 g of this sheet to a two-roll mill, and
Mix for minutes. This two roll mill is 325 ° F (163 ° C)
Set roll temperature. The mixed sheet was taken out of a two-roll mill in the form of a smooth heat-plasticized sheet. This sheet had a thickness of about 90 mils (2.3 mm).

A 90 mil (2.3 mm) sheet was compression molded to form a sample having a thickness of about 75 mil (1.9 mm). Compression molding was performed by the following continuous method using hydraulic pressure.
(A) Heat for 3 minutes at a temperature of 350 ° F. (177 ° C.) and a pressure of 0 lb / inch ² ; (b) 3 minutes at the same temperature and a pressure of 500 lb / inch ² (351,535 kg / m ² ). Heating; and (c) keeping the pressure at 351,535 kg / m ² and pressing the water (approximately
F or 21 ° C). Test bar pieces were cut from the samples for the tests described below.

Test Method Membrane Blocking Test Two test bar pieces (strips) of 2 inches x 6 inches (5.1 cm x 15.2 cm) are used for this test. The strip is placed one on top of the other and on a suitable support, for example a plate, in a forced air convection oven. At one end of the strip, a separating sheet, such as a polyethylene film, is sandwiched between the strips so that they do not make contact about 2 inches. A metal block 2 inches (5.1 cm) long and weighing 4 pounds (1.8 kg) is placed on the strip at the opposite end of the separator sheet and placed 2 inches x 2 inches (5.1 cm x 5.1 cm).
cm). This oven is 200 ゜ F
(93.3 ° C) set temperature. This strip, along with the block and separation strip, is placed in an oven at set temperature for 1 hour.

After one hour, the block is removed from the strip and the strip is removed from the oven. The strip is then transferred into a cooling chamber where ASTM standard conditions are maintained. ASTM standard conditions are 23 ± 2 ° C. and 50 ± 5% humidity. The strip is left in the cooling chamber for 24 hours.

After cooling, the strip is removed from the cooling chamber. The end of the strip separated by the separating sheet is placed at the entrance of the tensile tester and pulled off at a speed of 5 inches / minute (2 cm / minute). The force (in pounds) required to peel the strip is divided by the width (in inches) of the strip to give a "membrane blocking value".

Standard Tests for Membrane Formulations A. Low Temperature Brittleness-ASTM Test T Using Type T-50 Specimens
-746.

B. ASTM Test D-412-80 Method A using strips of ultimate tensile strength -2 inches x 1 inch (5.1 x 2.5 cm). The strip was placed in an Instron tensile tester with a 0.5 inch (1.3 cm) gap and 20 inches (50.8 c
m) / min crosshead speed.

C. Hardness, Shore A-SATM D-2240 D. 100% Modulus-ASTM D-412-80, Method A E. Tensile Strength (Type C)-ASTM-624 F. Melt Viscosity-Temperature of 190 ° C and 145 Measured with a capillary rheometer with a capillary size of 0.05 x 2 inches (0.13 x 5.08 cm) at a reciprocating second shear rate.

G. Heat of fusion 360-420 ゜ K or 32 at heating rate of 10 ゜ K / min
Measured by a differential scanning calorimeter at a temperature of 0 to 420 ° K [Example 6 (Table II only)].

Standard test for wire and cable formulations Test bar specimens prepared as described above were
Test by ASTM test method.

a. 100 percent modulus-ASTM D-412-80; b. ultimate tensile strength-ASTM D-412-80; c. elongation-ASTM D-412-80; d. melt viscosity-temperature of 190 ° C and 145 Measured with a capillary rheometer with a capillary size of 0.05 x 2 inches (0.13 x 5.08 cm) at a reciprocating second shear rate.

Examples 1-10 and Comparative Examples A-I-Preparation of Chlorinated Polyethylene Resin To prepare many chlorinated polyethylene resins, see Example 3
The chlorination method described herein was used except for the above. In Example 3, the rate of addition of chlorine gas was half that of the other Examples and Comparative Examples. Table II shows the polyethylene starting materials,
3 shows selected physical properties of the chlorinated resin.

Some of the chlorinated polyethylene resins shown in Table II are
Roof membrane samples were processed using the methods set forth herein. Table III shows the results of the physical property test of this sample.

The data shown in Tables II and III show the suitability of the chlorinated polyethylene resins of the present invention and distinguish them from the resins of Comparative Examples AF. The resins of Comparative Examples AF are unsatisfactory for a number of reasons. Comparative Examples B, D and E have low temperature brittleness values of -25 ° C or higher. Comparative Examples C and F have too high a viscosity to be processed into a roof membrane using conventional equipment. Comparative Example A is not a semi-crystalline resin. Comparative Example A also has a significantly higher blocking value. Similar satisfactory results are obtained with other chlorinated polyethylene resins typical of the present invention.

Evaluation of physical properties of wire and cable blends Many wire and cable blends are manufactured and tested.
Processed into a bar sample and adjusted the physical properties shown above
Solid. The test results are shown in Table IV. Resins marked "T"
Is Tyrin 2552.

The data shown in Table IV show the beneficial effects of mixing one of the chlorinated polyethylene resins of the present invention with a conventional semi-crystalline chlorinated polyethylene resin. This data shows that the processability was improved in terms of low viscosity without significantly reducing the desired physical properties. The same advantages are obtained with other chlorinated polyethylene resins within the scope of the present invention.

Claims (8)

(57) [Claims] 1. A semi-crystalline chlorinated polyethylene resin obtained by chlorinating a polyethylene resin having a viscosity of from 200 to 900 Pa · s (2,000 to 9,000 poises), wherein the chem. Combined chlorine content, heat of fusion of 7.5-16 calories / g, temperature of 190 ° C and 14
A melt viscosity of 500 to 1100 Pa · s (5,000 to 11,000 poise), a 100 percent modulus of 1.0 to 5.2 megapascals (150 to 750 pounds per square inch), measured with a capillary rheometer at a reciprocating shear rate of 5 seconds, and- 25 ℃
A semi-crystalline chlorinated polyethylene resin having a compounded low temperature brittleness value of less than. 2. The semi-crystalline chlorinated polyethylene resin of claim 1 wherein said chemically bound chlorine content is 23 to 30 weight percent of the polymer. 3. The semi-crystalline chlorinated polyethylene resin of claim 1 wherein said chemically bound chlorine content is 24 to 26 weight percent of the polymer. 4. The semi-crystalline chlorinated polyethylene resin according to claim 1, wherein said heat of fusion is 8 to 14 calories / g. 5. The melt viscosity is 550 to 1,000 Pa · s,
The semi-crystalline chlorinated polyethylene resin according to claim 1. 6. The polyethylene resin before chlorination is 300 to 8
The semi-crystalline chlorinated polyethylene resin according to claim 1, which has a viscosity of 50 Pa · s. 7. The semi-crystalline chlorinated polyethylene resin of claim 1, wherein said low temperature brittleness value is less than -30 ° C. 8. The method according to claim 1, wherein said 100 percent modulus is 2.4 to 4.5.
Megapascals (350-650 pounds per square inch)
The semi-crystalline chlorinated polyethylene resin according to claim 1.