JPH011748A - polymer blend composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. Field of Application The present invention relates to polymer blend compositions exhibiting excellent antistatic properties and improved flexibility. In particular, the present invention relates to polymer blend compositions consisting of styrenic polymers, epihalohydrin copolymers, and acrylate polymers.

[Background of the Invention J: (] Compositions containing styrenic polymers, such as ABS resins, are widely used because of the high impact strength, tensile strength and hardness, as well as the thermoplasticity of styrenic polymers.

However, many compositions containing styrenic polymers exhibit relatively slow static charge dissipation rates, making them unacceptable for applications requiring rapid dissipation of static charge.

Techniques have been developed to reduce static charge retention in polymer compositions. According to one method, articles molded from the polymeric composition are coated with an antistatic film coating material.

According to another method, electrostatic charge retention in a polymer composition is
This can be reduced by incorporating a substance with antistatic IF properties into the polymer composition. For example, U.S. Pat. No. 3,425,981 to PuleLlic et al. discloses polymer compositions containing homopolymers and copolymers of ethylene oxide to reduce static charge retention; (Ebncjh cL al) U.S. Patent No. 3,
No. 450,794 Specification i! P discloses a polymer composition containing polypropylene glycol. rlJ
U.S. Patent Nos. 4 and 5 of Tanaka et al.
No. 43,390 discloses an antistatic polymer composition comprising an ultrafine particle polymer consisting of a kraft copolymer of a polyalkylene oxide and a vinyl chloride of at least -Lm.

Fcderl et al., U.S. Pat. No. 4,588,773, discloses an improved band consisting of less than 80 wt% ABS graft copolymer and more than 20 wt% epihalophytrine copolymer). ``An inhibitory polymer composition is disclosed. The polymer composition disclosed by Fedel et al.
It shows the rate of charge decay from 000 volts to 0 volts. The ability of these compositions to quickly dissipate static charges makes these polymer compositions particularly advantageous for use in many applications.

However, the applicant has found that the propensity for delamination and low tensile elongation of the polymer compositions disclosed by Fedel et al. are in some cases inferior to other polymer compositions containing ABS polymers, and therefore The use of these compositions in a variety of applications has been found to be limited.

[Object 1 of the Invention] It is an object of the present invention to provide a polymer blend composition that exhibits excellent antistatic properties along with improved flexibility as demonstrated by reduced delamination and tensile elongation. In particular, one object of the present invention is to provide a polymer blend composition that exhibits rapid dissipation of static charge, as well as improved flexibility and reduced tendency to delaminate as indicated by increased tensile elongation at break. be.

SUMMARY OF THE INVENTION These and additional objects are achieved by the polymer blend composition of the present invention consisting of a styrenic polymer, an epihalohydrin copolymer, and an acrylate polymer. The acrylate polymer has a 7i1 of sufficient 7i1 to increase the compatibility of the styrenic polymer and the epihalophytrine copolymer compared to a blend of the styrenic polymer and the epihalohyline copolymer that does not contain the acrylate polymer. Contained in the blend composition. The increase in compatibility is evidenced in part by the increase in flexibility as indicated by tensile elongation. More preferably, the polymer blend compositions of the present invention exhibiting excellent antistatic properties and improved flexibility have a molecular weight of about 40 to about 9
It consists of 6% by weight styrenic polymer, about 2% to about 50% by weight epihalophytrine copolymer, and about 2% to about 50% by weight acrylate polymer. In a more preferred embodiment, the composition includes from about 55 to about 90% by weight styrenic polymer, from about 5 to about 25% by weight epihalohydrin copolymer, and from about 5 to about 25 In 71% acrylate polymer. .

The above and additional molding properties of the polymer blend compositions of the present invention will be more fully understood from the detailed description below.

DETAILED DESCRIPTION The polymer blend composition of the present invention consists of a styrenic polymer, an epihalohydrin copolymer, and an acrylate polymer. The acrylate polymer has an M sufficient to increase the compatibility of the styrenic polymer and the epihalohydrin copolymer compared to a blend of the styrenic polymer and the epihalohydrin copolymer that does not contain the acrylate polymer, and the polymer blend composition contained within.

The polymer blend composition has high impact strength and hardness;
In addition, styrenic polymers generally have thermoplastic q2
To demonstrate the properties, the styrenic polymer is preferably included in the polymer blend compositions of the present invention in an amount of about 40 to about 96 weight percent. Additionally, to provide the polymer blend composition of the present invention with antistatic properties and the ability to quickly dissipate static charges, it is preferred that the epihalohydrin copolymer be present at about 2% to about 50% IIt by weight. Additionally, in order for the polymer blend compositions of the present invention to exhibit improved flexibility, the acrylate polymer is included in the compositions at from about 2 to about 50 wt% Ut.
It is preferable that In a more preferred embodiment, the polymer blend compositions of the present invention include about 55 to about 90 weight percent styrenic polymer, about 5 to about 25 weight percent shrimp herrohydrin copolymer, and about 5 to about 25 weight percent shrimp herrohydrin copolymer. % by weight of acrylate polymer. The total amount of each component contained in the polymer blend composition of the present invention is 1001
n%.

Styrenic polymers useful for purposes of the present invention are polymers or copolymers of styrene, including both rigid resins and resins commonly referred to as high impact styrenic resins. High impact styrenic resins are generally made by graft polymerization of a mixture of styrene and optionally one or more additional copolymerizable vinyl monomers in the presence of a rubbery polymer. Similar resins can also be made by blending a hard matrix polymer with a grafted rubbery substrate such as High Rubber Graft. Generally, high rubber grafts contain a high percentage of rubber, such as 30% or more, preferably 40% or more, as is known in the art, used as grafting monomers. Similarly, comonomers used in admixture with styrene in the preparation of rigid styrene copolymers include vinyl alkyl hexanes such as alpha-methylstyrene, halostyrenes, vinyltoluene, vinylxylene, butylstyrene, and the like. In high impact styrenic resins, the rubbery polymeric substrate is generally a graft polymer. from the group consisting of polybutadiene, polyisoprene, rubbery styrene-diene copolymers, acrylic rubbers, nitrile rubbers, and olefin rubbers such as EPDM, EPR. Additionally, other styrenic polymers known in the art can be used in the blend compositions of the present invention.

Particular examples of graft polymers that are useful modified for the purposes of this invention are acrylonitrile-butadiene-styrene graft polymer resins (ABS), methyl methacrylate-butadiene-acrylonitrile-styrene resins (MABS), styrene-butadiene Graft polymer resin (HIPS) and methyl methacrylate
Butadiene-styrene resin (MBS). Particular examples of styrene polymers that are useful and modified for the purposes of this invention include polystyrene, copolymers of styrene such as styrene-acrylonitrile copolymers (SAN), styrene-methacrylate ester copolymers, styrene-acrylonitrile-anhydrous Includes maleic acid terpolymer resins (SAMA), styrene-maleic anhydride copolymer resins (SMA), similar bombers containing maleimides and the like containing N-phenyl and other substituents, and mixtures thereof. .

Additionally, similar copolymer resins in which a portion of the styrene monomer component is replaced with other styrenic agents such as alpha-methylstyrene, halogenated styrene or vinyltoluene may also be used. Blends of styrenic polymers with one or more of polyphenylene ethers, polyvinyl chloride polymers, polyamides, polycarbonates, and other polymers commonly known in the art for blending with styrenic polymers can also be used. These additional polymers are generally known in the art and are described in the Modern Plastics Encyclopedia (Mo
dern PlasLics Encyclopedi
a), 1986-1987McGraw-11i11
Inc., New York.

A tale revealed in New Yorkl'll.

A preferred styrenic polymer in the present invention is ABS
Graft copolymer, high impact polystyrene,
Polymethyl methacrylate-styrene-acrylonitrile-butylene graft copolymer, blend of polystyrene and polyphenylene ethyl, high rubber graft polymer and styrene-acryloni-1-lyl-maleic anhydride polymer and/or styrene-maleic anhydride. polymers, etc.

Engineered halohydrin copolymers are included in the polymer blend compositions of the present invention to provide compositions with excellent antistatic properties. Epihalohydrin can be copolymerized with various known copolymerizable polymers having oxirane groups. Such substances include glycidyl ether,
Included are monoepoxides, glycidyl esters and alkylene oxides of dienes and polyenes. Specific examples of such substances include vinyl glycidyl ether, isopropenyl glycidyl ether, butadiene monoxide, chlorobrene monoxide, 3,4-epoxy-1-pentene, guawashyl acrylate, glycidyl methacrylate, 1. 2-Epoxy-3,3,3
- trichloropropane, phenyl glycidyl ether,
Includes ethylene oxide, propylene oxide, and trichlorobutylene oxide.

Preferably, the monomer is ethylene oxide, propylene oxide, butylene oxide, 3,4-epoxy-1-pentene, 1,2-epoxy-3,3,3-
) Lichlorobroban, trichlorobutylene oxide,
and the like. More preferably, the alkylene oxide is ethylene oxide, propylene oxide or a mixture thereof.

Ethylene oxide is most preferred.

In a preferred embodiment, the epihalohydrin and alkylene oxide are copolymerized to form an epihalohydrin rubber prior to combination with the styrenic polymer. Suitable epihalohydrin copolymers are commercially available or can be prepared from known commercially available monomers using known techniques. - Structurally, epihalohydrin copolymers contain from about 2 to about 98 weight percent epihalohydrin and from about 98 to about 2 weight percent other monomers. More preferably, the copolymer has a molecular weight of about 5 to about 5021
, j (1% by weight epihalohydrin and from about 95 to about 50% by weight of another, preferably alkylene oxide). In the most preferred embodiment, the copolymer contains from about 10 to about 40% by weight epihalohydrin. , about 9
0 to about 60% by weight of other additives.

A preferred epihalohydrin copolymer is a copolymer of epichlorohydrin and ethylene oxide.

To provide a composition with improved flexibility, the acrylate polymer contained in the polymer blend composition of the present invention consists of an acrylate homopolymer or an acrylate copolymer. If an acrylate copolymer is used, it is preferred that the copolymer is formed from greater than 50% by weight of acrylate monomer. Preferred acrylate polymers include acrylate homopolymers such as polyalkyl acrylates and polyalkyl methacrylates, as well as charged (e.g.
acrylate copolymer containing less than 4%) of acrylate comonomer. A particularly preferred acrylate polymer for use in the present invention consists of polymethyl methacturate.

Blend compositions of the present invention can be made by combining styrenic polymers, epihalohydrin polymers, and acrylate polymers by any method known in the art. For example, by melt mixing the polymer components using a Banbury Mixer 1 extruder, or a mill.
Polymers can be combined to form blended compositions. Impact modifiers, pigments, lubricants, stabilizers, fillers,
Other known additives such as flame retardant IL agents, blowing agents, and antioxidants can also be included in the polymer blend composition.

In order to improve the flexibility and compatibility of blends of styrenic polymers and epihalohydrin polymers, I
The acrylate polymers disclosed in F. also include epihalohydrin polymers and other thermoplastic polymers, such as
It can be used to improve the flexibility and/or compatibility of blends with polyphenylene ethers, polyvinyl chloride, polycarbonates, thermoplastic polyesters, polysulfones, and the like.

[Actual hh Example 1] A styrenic polymer was produced by blending 47 parts of styrene-acrylonitrile copolymer (styrene to acrylonitrile weight ratio 75/25) with 1 part of High Rubber Graft Copolymer 231E↓ was manufactured. A copolymer of epichlorohydrin and ethylene oxide having an approximate weight ratio of 20% epichlorohydrin and 80% ethylene oxide is added to this mixture.
5 parts by weight, and 15 parts by weight of polymethyl methacrylate. The mixture was compounded in a Banbury mixer, then injection molded at 221"C (430F) and evaluated for mechanical properties and electrostatic charge dissipation (ESD) properties. Specifically, surface resistance, percent tensile elongation. , and relative humidity 15
% and 50%, the static charge dissipation rate from V to O volts was measured in 5, and the results are shown in Table 1.

[Example 2] Instead of the styrene-acrylonitrile copolymer of Example 1, a different styrene-acrylonitrile copolymer (
A composition was prepared as described in Example 1, except that a styrene to acrylonitrile ratio of 72/28) was used. The resulting moldings were tested for surface resistance, percent tensile elongation, and static '1' as described in Example 1.
``The load depletion rate was determined to be 1l11.The results are shown in Table 1.

[Example 3] Rubber-like J, t, a styrenic polymer 701'j ij part consisting of a copolymer of acrylonitrile and styrene grafted onto the body, 1 part: 15 parts of the epichlorohydrin copolymer of Example 1, and 1 part of the epichlorohydrin copolymer of Example 1. A polymer blend composition of the present invention was prepared by combining 15 parts by weight of polymethyl methacrylate. The resulting mixture was blended in a Banbury mixer and mixed at 221"C (4
injection molded at 30°F). Regarding the obtained molded product,
Surface resistance, percent tensile elongation, and static charge dissipation rate were measured as described in Example 1. The results are shown in the schedule.

[Example 4] Styrene, v-ABS polymer (styrene of Example 2)
By combining 52 parts of acrylonitrile copolymer and 23 parts of high rubber substrate of Example 1), 75 parts by weight of epichlorohydrin copolymer of Example 1, and 75 parts of polymethyl methacrylate of Example 1, the present invention A preferred polymer blend composition was prepared. The resulting mixture was compounded in a Banbury mixer and injection molded at 221°C (430'F). The resulting moldings were prepared as described in Example 1. The surface resistance, percent tensile elongation, and static charge dissipation rate were measured.The results are shown in Table 1.

Comparative Example 1: Polymer blend composition consisting of an ABS polymer comprising 62 parts by weight of the styrene-acrylonitrile copolymer of Example 2 blended with 23 parts by weight of the high rubber graft copolymer, and 15 parts by weight of the epichlorohydrin copolymer of Example 2. was manufactured. The mixture was compounded in a Banbury mixer and injection molded at 430'F. The resulting moldings were tested as described in Example 1 to determine surface resistance, percent tensile elongation,
and the rate of static charge disappearance was measured. The results are shown in the schedule.

These Examples and Comparative Examples show that the band' of the composition of the present invention, i': l'j
The results show that the antistatic properties and electrostatic charge resistance are comparable to or superior to those of comparative compositions that do not contain acrylate polymers. The polymer blend compositions of the present invention exhibit significantly improved flexibility as shown by percent tensile elongation measurements from stiffness to break. As such, the polymer blend compositions of the present invention are particularly adapted for use in applications where excellent static protection or static charge dissipation properties and excellent flexibility are required.

Examples 5-9 Polymer blend compositions consisting of high impact polystyrene (HIPS), epichlorohydrin-ethylene oxide copolymer and polymethyl methacrylate were prepared according to the present invention. 1.1 of each component contained in the compositions of Examples 5 to 9 is shown in Table 2. These compositions were heated to 218°C (425°F) in a twin screw extruder.
and injection molded at 221°C (430°F). Next, the obtained molded article was tested and its mechanical properties and static charge dissipation properties were evaluated. In particular, molded products were subjected to tensile elongation, yield point, and elastic modulus measurements, and Dynatap (DynaTap)
t, upR) Dirt impact and notched isot impact measurements were performed. Static charge dissipation was measured as the decay time from 5000 volts to 0 volts at 11% relative humidity. Same ASTM as described with respect to Examples 1-4
The method was applied to the molded articles of Examples 5-9. The results of these measurements are shown in Table ①.

[Comparative Example 2] High impact polystyrene 85 fl'j-71 parts used in Examples 5 to 9 and epichlorohydrin-ethylene oxide copolymer 1 used in Examples 5 to 9
A polymer blend composition containing five leaflets was produced. The composition was twin screw extrusion compounded at 218°C (425°F) and injection molded at 221°C (430°F).

The resulting molded articles were then subjected to tensile elongation, yield point, and elastic modulus measurements as described in Examples 5 to 9, as well as DynaLup'' dart impact and notched isot impact measurements. In addition, the molded articles of the composition were subjected to the static charge dissipation property +if' value as described in Examples 5 to 9. The results of these measurements are shown in Table 2.

[Comparative Example 3] A polymer blend composition consisting of 100 parts by weight of the high impact polystyrene used in Examples 5 to 9 was produced. This polymer composition was subjected to the molding treatment described in Examples 5 to 9, and the resulting molded article was then subjected to the molding treatment described in Examples 5 to 9.
The specimens were subjected to tensile elongation, yield point, elastic modulus measurements, impact measurements, and static charge dissipation measurements as described in . The results of these measurements are shown in Table ①.

In the following margin Examples 5 to 9, styrenic polymer,
For a polymer blend composition containing an epichlorohydrin copolymer and polymethyl methacrylate,
It shows significant improvement in flexibility as expressed in percent tensile elongation, dart impact and isot impact values. Additionally, Examples 5-9 demonstrate the significant static charge dissipation properties of the polymer blend compositions of the present invention compared to the high impact polystyrene control composition of Comparative Example 3, which did not contain epichlorohydrin copolymer or polymethyl methacrylate. It shows. Examples 5-9
and all the compositions of Comparative Examples 2 and 3 had 109 to 10
It exhibited a surface resistance within the range of 1:I ohm (area).

Example 10 This example demonstrates a polymer blend composition of the present invention containing high impact polystyrene, epichlorohydrin copolymer and polymethyl methacrylate. Specifically, the composition consisted of 70 parts by weight of high impact polystyrene, 15 parts by weight of the epichlorohydrin-ethylene oxide copolymer described in Example 1, and 1 part by weight of polymethyl methacrylate. The composition includes:
It also contained 5 parts by weight of a rubber modifier. The compositions were mixed, injection molded into molded articles, and then tested to evaluate their mechanical properties and static charge dissipation. especially,
The molded article was subjected to tensile elongation as described in Examples 5 to 9,
It was subjected to isot impact and dart impact measurements, and static charge dissipation measurements as described in Examples 5 to 9. The molded article of the composition of this example had a tensile elongation of 32% and a notched Izot impact of 3.2 ft-1t.
+s/in, DynaLupR dirt impact 14.0ft-1bs. Further, the static charge dissipation time from 5000 volts to O volts at 11% relative humidity was 1.8 seconds. Thus, compositions of the present invention containing high impact polystyrene with rubber modifier, polyepichlorohydrin copolymer and polymethyl methacrylate exhibited both improved flexibility and increased static charge dissipation.

[The examples shown below are illustrative of particular embodiments of the invention and are not intended to limit the scope of the compositions and methods of the invention. Other embodiments and advantages within the scope of the invention will be apparent to those skilled in the art.

Patent applicant Pogoo Warner Chemicals, Inc. Representative Patent attorney Yasushi Yanagawa

Claims (1)

[Claims] 1. A styrenic polymer and an epihalohydrin copolymer as compared to a blend of a styrenic polymer and an epihalohydrin copolymer that does not contain (a) a styrenic polymer, (b) an epihalohydrin copolymer, and (c) an acrylate polymer. A polymer blend composition characterized in that it consists of an acrylate polymer present in an amount sufficient to increase compatibility with the copolymer.