KR20140125726A - Low particle size polyethylene, its chlorinated polyethylene and pvc composition containing the same - Google Patents

Abstract

The present invention relates to polyethylene, chlorinated polyethylene thereof, and a PVC composition containing the same, and more specifically, to polyethylene, which has an average particle size of 30-170 μm, a melt index (5.0 kg) of 0.001-100, a weight average molecular weight of 50,000-300,000, a molecular weight distribution (MWD) of 20 or less, a melting point of 125-140°C, and a density of 0.94 g/cm^3 or more and is used for preparing chlorinated polyethylene, to chlorinated polyethylene thereof, and to a PVC composition containing the same. According to the present invention, there is an effect of providing polyethylene having excellent chlorine distribution uniformity in polyethylene during chlorination, chlorinated polyethylene having excellent compatibility with PVC, excellent impact reinforcement performance, and remarkably reduced fusion time, and a PVC composition having excellent impact strength, processability, and productivity.

Description

TECHNICAL FIELD [0001] The present invention relates to a low-particle-size polyethylene, a chlorinated polyethylene thereof, and a PVC composition comprising the same. BACKGROUND OF THE INVENTION [0002]

The present invention relates to a low-particle-size polyethylene, a chlorinated polyethylene thereof and a PVC composition comprising the same, and more particularly to a low-particle-size polyethylene which is excellent in chlorine distribution uniformity in polyethylene during chlorination; Chlorinated polyethylene which is excellent in compatibility with PVC and impact reinforcing performance and greatly shortens the fusing time; And a PVC composition excellent in impact strength, processability and productivity.

Polyethylene is a chain-like polymer produced by the polymerization of ethylene and is classified into low density polyethylene (LDEP) and high density polyethylene (HDPE) depending on the density.

High density polyethylene can generally be prepared by polymerizing ethylene at about 70 캜 and 10 atm using a Ziegler-Natta catalyst.

High-density polyethylene is excellent in softening point, hardness, strength and electrical insulation, and is used in various containers, packaging films, fibers, pipes, packings, insulating materials and the like.

Chlorinated polyethylene is chlorinated by treatment of polyethylene with chlorine.

Chlorinated polyethylene is generally prepared by reacting polyethylene with chlorine in suspension, or by reacting polyethylene with chlorine in aqueous HCl.

Chlorinated polyethylene is widely used as an impact modifier for PVC pipes and window profiles because it has excellent chemical resistance, weather resistance, flame retardancy, workability and impact strength.

It is an object of the present invention to provide a polyethylene which is excellent in chlorine distribution homogeneity in polyethylene during chlorination.

In addition, the present invention aims to provide chlorinated polyethylene which is excellent in compatibility with PVC and impact reinforcing performance and greatly shortens the fusing time.

Further, the present invention aims to provide a PVC composition excellent in impact strength and processability.

These and other objects of the present disclosure can be achieved by all of the present invention described below.

In order to achieve the above object, the present invention relates to a thermoplastic elastomer composition having an average particle size of 30 to 170 탆, or 30 to 150 탆, a melt index (5.0 kg) of 0.001 to 20, or 0.01 to 100 and a weight average molecular weight of 10,000 to 1,000,000 g / mol and a molecular weight distribution (MWD) of 20 or less, or 3 to 20, a melting temperature of 125 to 140 DEG C and a density of 0.94 g / cm < .

The present invention also relates to a thermoplastic resin composition having an average particle size of 50 to 150 탆 or 50 to 130 탆, a melt index (5.0 kg) of 0.001 to 5, or 0.1 to 10, a weight average molecular weight of 50,000 to 300,000 g / Wherein the polyethylene has a distribution (MWD) of 3.5 to 15, or 10 or less, a melting temperature of 125 to 140 占 폚, and a density of 0.94 g / cm3 or more, for use in the production of chlorinated polyethylene.

In addition, the present disclosure provides chlorinated polyethylene produced from the polyethylene.

The present disclosure also provides a PVC composition comprising the chlorinated polyethylene and the vinyl chloride polymer (PVC).

As described above, according to the present invention, low-grade polyethylene which is excellent in chlorine distribution homogeneity in polyethylene during chlorination; Chlorinated polyethylene which is excellent in compatibility with PVC and impact reinforcing performance and greatly shortens the fusing time; And a PVC composition excellent in impact strength, processability and productivity.

Hereinafter, the polyethylene of the present invention, its chlorinated polyethylene and the PVC composition containing the same will be described in detail.

The polyethylene of the present invention has an average particle size of 30 to 150 占 퐉, a melt index (5.0 kg) of 0.01 to 100, a weight average molecular weight of 10,000 to 1,000,000 g / mol, a molecular weight distribution (MWD) of 3 to 20, Characterized in that it is used in the production of chlorinated polyethylene at a temperature of 125 to 140 DEG C and a density of 0.94 g / cm < 3 > or more.

For example, the polyethylene of the present invention has a low-particle-size polyethylene content of 150 μm or less in a range of 20 to 100% by weight, 50 to 90% by weight, or 60 to 90% by weight, and the chlorine distribution uniformity in the polyethylene And when it is applied as an impact modifier to PVC, impact reinforcing performance, plasticizing speed and productivity are greatly improved.

Another example of the average particle size of the polyethylene of the present invention is 50 to 150 mu m, 70 to 150 mu m, 90 to 130 mu m, or 50 to 130 mu m. In this range, uniformity of chlorine distribution in the polyethylene is excellent, The impact reinforcing performance, the plasticizing speed and the productivity are greatly improved.

As another example of the polyethylene of the present invention, the melt index (5.0 kg) is 0.1 to 10, 0.1 to 3.0, or 0.1 to 2.0, and the reinforcing effect is excellent in this range.

Another example of the polyethylene of the present invention has a weight average molecular weight of 50,000 to 300,000 g / mol, 100,000 to 250,000 g / mol, or 150,000 to 250,000 g / mol.

Another example of the polyethylene of the present invention has a molecular weight distribution (MWD) of 3.5 to 15, or 4 to 10, and when applied as an impact modifier in PVC, the plasticization rate and productivity are greatly improved.

Another example of the polyethylene of the present invention is a melt temperature of 130 to 140 占 폚, or 130 to 136 占 폚.

Another example of the polyethylene of the present invention has a density of 0.94 to 0.960 g / cm3.

The polyethylene of the present disclosure can be, for example, a comonomer-free polyethylene that does not contain a comonomer.

The production of the chlorinated polyethylene may be carried out, for example, by the hydrothermal method or the acid method, and in this case, the CPE chlorination time and the post treatment time such as neutralization and washing are greatly shortened.

The polyethylene of the present invention can be prepared, for example, by reacting an ethylene monomer in a continuous stirred reactor (CSTR) with a catalyst under a molecular weight regulator.

The molecular weight regulator may be, for example, hydrogen.

The catalyst can be, for example, a Ziegler-Natta catalyst or a Ziegler-Natta catalyst diluted in a solvent.

For example, the Ziegler-Natta catalyst may have an average particle size of 3 to 10 μm or 5 to 8 μm. Within this range, polyethylene having a low particle size and a constant molecular weight distribution (MWD) can be efficiently obtained.

The chlorinated polyethylene of the present invention is characterized in that it is produced from the polyethylene of the present invention.

The chlorination can be carried out, for example, by the hydrothermal method or the acid method, and in this case, the chlorine distribution in the chlorinated polyethylene is uniform, thereby improving the elasticity of CPE produced.

For example, the acid method is a method in which an aqueous acid solution such as an aqueous solution of hydrochloric acid (HCl) is chlorinated by using an emulsifying agent and a dispersing agent. The aqueous solution is chlorinated by using an emulsifier and a dispersing agent together with water.

The chlorinated polyethylene may have a chlorine content of 20 to 45% by weight, 31 to 40% by weight, or 33 to 38% by weight, for example.

The chlorinated polyethylene may be, for example, random chlorinated polyethylene.

The chlorinated polyethylene has a volume resistance of 10 ¹³ to 10 ¹⁷ ? Cm, 10 ¹⁴ to 10 ¹⁷ ? Cm, or 10 ¹⁵ to 10 ¹⁶ ? Cm, for example.

The chlorinated polyethylene has a thermal stability of, for example, 160 to 180 ° C or 170 to 175 ° C, and has an effect of not being decomposed well when used in the crosslinking reaction within this range

The chlorinated polyethylene has an MDR crosslinking torque of 1.0 to 3.0 Nm or 1.5 to 2.5 Nm, for example, and has an excellent crosslinking density and tensile strength within this range

The chlorinated polyethylene of the present invention can be produced, for example, by dispersing polyethylene with water, an emulsifying agent and a dispersing agent, and then adding a catalyst and chlorine to react.

The emulsifier is, for example, polyether or polyalkylene oxide.

The dispersing agent is, for example, a polymer salt or an organic acid polymer salt.

The organic acid may be, for example, methacrylic acid, acrylic acid, or the like.

The catalyst is, for example, a chlorination catalyst, and another example is a peroxide or an organic peroxide.

The chlorine may be used alone or in combination with an inert gas.

The final chlorination temperature is, for example, 60 to 150 ° C, 70 to 145 ° C, 90 to 140 ° C, or 130 to 137 ° C.

The chlorination reaction time is, for example, 10 minutes to 10 hours, 1 to 6 hours, or 2 to 4 hours.

As another example of the chlorinated polyethylene, 100 parts by weight of polyethylene, 0.01 to 1.0 part by weight or 0.05 to 0.5 part by weight of an emulsifier and 0.1 to 10 parts by weight or 0.5 to 5.0 parts by weight of a dispersant are dispersed in water, By weight or 0.05 to 0.5 parts by weight of chlorine and 80 to 200 parts by weight or 100 to 150 parts by weight of chlorine.

The chlorinated polyethylene produced by the reaction or chlorination process can be obtained, for example, by neutralization, washing, and drying to obtain powdered chlorinated polyethylene.

For example, the neutralization step may be a step of neutralizing the reactant after the chlorination step with a base solution at 70 to 90 ° C or 75 to 80 ° C for 4 to 8 hours.

The PVC composition of the present invention is characterized in that it comprises chlorinated polyethylene and vinyl chloride polymer (PVC) of the present invention.

The PVC composition may comprise, for example, from 1 to 40% by weight of the chlorinated polyethylene of the present invention and from 60 to 99% by weight of a vinyl chloride polymer (PVC).

The chlorinated polyethylene may be, for example, 1 to 15% by weight, or 5 to 10% by weight.

The vinyl chloride polymer (PVC) may be, for example, 85 to 99% by weight, or 90 to 95% by weight.

In another example, the PVC composition of the present invention comprises 1 to 20% by weight of chlorinated polyethylene, 70 to 90% by weight of a vinyl chloride polymer (PVC), 1 to 10% by weight of TiO _2, 1 to 10% by weight of CaCO ₃ , And 1 to 10% by weight of a complex stearate (Ca, Zn-stearate).

The PVC composition may have a plasticizing time of 170 seconds or less, 150 seconds or 150 to 100 seconds, an Izod impact strength of 100 kg · cm / cm or more, 125 kg · cm / cm or more, or 125 to 145 kg Cm < 2 > / cm, and has an excellent balance of physical properties and productivity in this range.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention within the scope and spirit of the following claims, Such variations and modifications are intended to be within the scope of the appended claims.

[Example]

Example  One

<High density polyethylene>

High density polyethylene (CE6040X, manufactured by LG Chemical) made of a Ziegler-Natta catalyst having an average particle size of 5.5 mu m was used. The high-density polyethylene is in the form of powder, and the average density, MI, MWD, melting temperature and density are shown in Table 1 below.

&Lt; Preparation of chlorinated polyethylene &

5,000 L of water and 550 kg of the high-density polyethylene were fed into the reactor, and then sodium polymethacrylate as a dispersant, oxypropylene and oxyethylene copolyether as an emulsifier, and benzoyl peroxide (benzoyl peroxide) was added, and chlorine was injected into the gas phase at 132 캜 for 3 hours.

The chlorinated reactant was neutralized for 4 hours by adding NaOH or Na ₂ CO ₃ , washed again with flowing water for 4 hours, and finally dried at 120 ° C to prepare powdered chlorinated polyethylene.

< PVC  Preparation of composition &gt;

The PVC composition was prepared by mixing 6.5 wt% of chlorinated polyethylene, 81.6 wt% of vinyl chloride polymer (PVC), 3.2 wt% of TiO ₂ , 4.1 wt% of CaCO ₃ and 4.5 wt% of complex stearate (Ca, Zn) .

Example  2

In Example 1, chlorinated polyethylene and PVC composition specimens were prepared in the same manner as in Example 1, except that HDPE prepared using a Ziegler-Natta catalyst having an average particle size of 3.5 μm as the high-density polyethylene was used.

Example  3

The chlorinated polyethylene and PVC composition specimens were prepared in the same manner as in Example 1, except that LG Chem CE6040K prepared using Ziegler-Natta catalyst having an average particle size of 8.5 μm as the high density polyethylene in Example 1 was used.

Comparative Example  One

In Example 1, chlorinated polyethylene and PVC composition specimens were prepared in the same manner as in Example 1, except that LG Chem CE6040 manufactured by using a high-density polyethylene and a Ziegler-Natta catalyst having an average particle size of 12 μm was used. The average density, MI, MWD, melting temperature and density, etc. of the high density polyethylene used in Comparative Examples 1 to 6 are shown in Table 2 below.

Comparative Example  2

A sample of chlorinated polyethylene and PVC composition was prepared in the same manner as in Example 1, except that HDPE having an average particle size of 220 탆 sold in the market as high density polyethylene in Example 1 was used.

Comparative Example  3

A chlorinated polyethylene and PVC composition specimen was prepared in the same manner as in Example 1, except that LG Chem CE2080 prepared using a Ziegler-Natta catalyst having an average particle size of 12 μm as the high density polyethylene in Example 1 was used.

Comparative Example  4

The chlorinated polyethylene and PVC composition specimens were prepared in the same manner as in Example 1, except that LG Chem 2020M manufactured by using a metallocene catalyst having an average particle size of 10 μm as the high density polyethylene in Example 1 was used.

Comparative Example  5

A chlorinated polyethylene and PVC composition specimen was prepared in the same manner as in Example 1, except that LG Chem KR2080T1 prepared using a Ziegler-Natta catalyst having an average particle size of 12 μm as the high density polyethylene in Example 1 was used.

Comparative Example  6

The chlorinated polyethylene and PVC composition specimens were prepared in the same manner as in Example 1, except that LG Chem 2030K manufactured by using Ziegler-Natta catalyst having an average particle size of 8.5 μm as the high-density polyethylene in Example 1 was used.

[Test Example]

The properties of the chlorinated polyethylene (CPE) and PVC composition samples prepared in Examples 1 to 4 and Comparative Examples 1 to 6 were measured by the following methods, and the results are shown in Tables 1 and 2 below.

* Melt Index (dg / min): Measured under the conditions of 190 캜 and 5 kg in accordance with ASTM D-1238.

* Weight average molecular weight (g / mol): Measured by gel permeation chromatography. The measuring instrument used was PL-GPC 220 from Agilent (Polymer Laboratories). The sample was prepared by adding 0.2 wt% of HDPE and 125 ppm of BHT to TCB (Trichlorobenzene) and then dissolving at 165 ° C for 2 hours. The sample was mixed with three Mixed-B Columns manufactured by Agilent (Polymer Laboratories) B Guard Column.

* Molecular weight distribution: Measured by the ratio (Mw / Mn) of the number average molecular weight (Mn) to the weight average molecular weight (Mw) measured by gel permeation chromatography.

* Melting temperature: Measured at a heating rate of 10 ° C / min using DSC.

* Low particle size (150 μm or less): Calculated in weight% using a sieve of 150 μm mesh.

* Average particle size: Particle size analyzer A total of 9 sieves (63 ~ 850 ㎛) were mounted on a Taylor type auto shaker to calculate the particle size corresponding to 50% of the total weight of the sample.

Density: Measured according to ASTM D-792.

* Chlorine content: The sample was burned at 1000 ° C using Automatic Quick Furnace, the gas was collected in H ₂ O and the Cl content was analyzed by IC (Ion Chromatograph) instrument.

* Plasticization time: It was measured as the time when PVC was melted and plasticization stabilized when PVC and chlorinated polyethylene were blended. Using a Thermo Haake, the temperature was measured at 170 ° C, a screw speed of 60 rpm, and a resin filling amount (PVC composition) of 63 g. The PVC composition consisted of 100 parts by weight of PVC, 8 parts by weight of chlorinated polyethylene, 4 parts by weight of TiO ₂ , 5.5 parts by weight of CaCO _{3 and} 5.5 parts by weight of composite stearate (Ca, Zn).

Izod impact strength (1/4 "notched at 0 ° C, kg · cm / cm): measured according to ASTM D256.

* Volume resistivity: Measure the volume resistivity of a CPE sheet with a measured area of 19.625 cm ³ and a specimen thickness of 0.2 cm according to ASTM D257 method.

* Thermal Stability: When the temperature of the oil bath was increased to 10 ° C per minute by adding the chlorinated polyethylene raw material to the test tube, the point of decomposition into HCl was measured.

Crosslinking Density: A sheet was prepared by mixing rolls of crosslinking agent, crosslinking aid, lubricant and cross-linking agent together with talc and calcium carbonate in chlorinated polyethylene at 130 ° C for 2 minutes and press molding at 150 ° C for 2 minutes. ASTM D- 2080, the scorch time and the curing rate were measured at 165 ° C.

division Example 1 Example 2 Example 3 PE Low particle content 75 85 53 Average particle size 120 95 145 MI (5kg) 0.9 0.8 0.45 Mw 175,000 185,000 200,000 MWD 5.5 5.5 5 Melting temperature 133 133 133 density 0.952 0.953 0.952 CPE Chlorine content 36 36 36 Volumetric resistance (* 10 ¹⁴ ) 170 240 130 Thermal stability 172 174 175 Bridging torque 2.0 2.1 2.3 PVC Plasticization time 140 130 150 Izod impact strength 125 130 145

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 PE Low particle content 30 20 23 25 25 53 Average particle size 180 220 200 200 200 145 MI (5kg) 0.45 0.5 1.3 3 0.35 1.7 Mw 200,000 205,000 180,000 140,000 270,000 160,000 MWD 5 5 12 2.8 13.5 24 Melting temperature 133 133 132 132 133 131 density 0.952 0.952 0.957 0.954 0.956 0.957 CPE Chlorine content 36 36 36 36 36 36 Volumetric resistance (* 10 ¹⁴ ) 83 62 5.2 90 13 1.2 Thermal stability 171 170 164 173 166 158 Bridging torque 1.8 1.7 1.4 1.6 1.7 1.2 PVC Plasticization time 180 190 90 180 150 70 Izod impact strength 145 140 86 130 95 73

As shown in Tables 1 and 2 above, the PVC compositions (Examples 1 to 3) comprising chlorinated polyethylene according to the present invention can be used for PVC compositions comprising chlorinated polyethylene made from polyethylene having an average particle size of 180 or 220 탆 Compared with Comparative Examples 1 to 5, it was confirmed that the plasticization time was greatly shortened (productivity was improved) and Izod impact strength was also excellent.

In the case of Comparative Example 6, the average particle size of the polyethylene used was 145 μm, but the MWD was 24, which was significantly different from the range of MWD of the polyethylene according to the present invention, and Izod impact strength was found to be poor.

Claims (18)

(MWD) of 3 to 20, a melting temperature of 125 to 140 占 폚, and a melt index (MWD) of 30 to 150 占 퐉, a melt index (5.0 kg) of 0.01 to 100, a weight average molecular weight of 10,000 to 1,000,000, Characterized in that it has a density of 0.94 g / cm &lt; 3 &gt; or more and is used for the production of chlorinated polyethylene
Polyethylene. The method according to claim 1,
Characterized in that the polyethylene has a low particle-size content of 150 μm or less in an amount of 20 to 100% by weight
Polyethylene. The method according to claim 1,
Wherein the average particle size is 50 to 130 탆
Polyethylene. The method according to claim 1,
Wherein the melt index (5.0 kg) is 0.1 to 10
Polyethylene. The method according to claim 1,
Wherein the weight average molecular weight is in the range of 50,000 to 300,000 g / mol
Polyethylene. The method according to claim 1,
Wherein the molecular weight distribution (MWD) is 3.5 to 15
Polyethylene. The method according to claim 1,
And the melting temperature is 130 to 140 ° C
Polyethylene. The method according to claim 1,
Wherein the density is 0.94 to 0.96 g / cm &lt; 3 &gt;
Polyethylene. The method according to claim 1,
The production of the chlorinated polyethylene is characterized in that it is based on an aqueous process or an acid process
Polyethylene. The method according to claim 1,
Characterized in that the polyethylene is produced by a Ziegler-Natta catalyst
Polyethylene. Characterized in that it is produced from the polyethylene of any one of claims 1 to 10
Chlorinated polyethylene. 12. The method of claim 11,
Characterized in that the chlorinated polyethylene is random chlorinated polyethylene
Chlorinated polyethylene. 12. The method of claim 11,
The chlorinated polyethylene has a chlorine content of 20 to 45% by weight
Chlorinated polyethylene. 12. The method of claim 11,
Characterized in that the chlorinated polyethylene has a volume resistance of 10 ¹³ to 10 ¹⁷ Ω cm, a thermal stability of 160 to 180 ° C. and a crosslinking torque of 1.0 to 3.0 Nm
Chlorinated polyethylene. Characterized in that it comprises the chlorinated polyethylene of claim 11 and a vinyl chloride polymer (PVC)
PVC composition. 16. The method of claim 15,
The PVC composition is characterized in that the plasticizing time is 170 seconds or less
Chlorinated polyethylene. 100 to 100 parts by weight of the polyethylene according to any one of claims 1 to 9, 0.01 to 1.0 part by weight of an emulsifier and 0.1 to 10 parts by weight of a dispersant are dispersed in water, 0.01 to 1.0 part by weight of a catalyst and 80 to 200 parts by weight of chlorine And then reacting
A method for producing chlorinated polyethylene. 18. The method of claim 17,
The reaction is characterized in that the final temperature is from 60 to 150 ° C
A method for producing chlorinated polyethylene.