JPS59227938A - Polymer composition - Google Patents

Abstract

PURPOSE:To prevent or reduce the emission of malodor during molding, by controlling the quantity of 1-methyl-4-ethenylbenzene remaining in a polymer compsn. composed of a methylethenylbenzene isomer mixture to a specified small value. CONSTITUTION:The quantity of 1-methyl-4-ethenylbenzene remaining in a polymer compsn. contg. a polymer comprising, a methylethenylbenzene isomer mixture (hereinafter referred to as PMS mixture) consisting of 0-0.1wt% 1-methyl- 2-ethenylbenzene, 0-15wt% 1-methyl-3-ethenylbenzene and not less than 85wt% 1-methyl-4-ethenylbenzene is controlled to 0.3-0.03wt% without resort to a reprecipitation/drying method. The emission of malodor from the resulting PMS polymer compsn. during processing at a high temp. is greatly reduced. The reprecipitation/drying method is disadvantageous in that the process is complicated, the resulting polymer compsn. exhibits poor flow characteristics during processing and the processing temp. must be raised. Thus, a volatile matter removal method is preferred.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polymer composition comprising a polymer having a mixture of isomers of methylethynylbenzene as a polymer constituent.

More specifically, the present invention relates to a methylethynylbenzene polymer composition that provides a favorable working environment during the processing of monopolymer compositions.

0 to 0-1% by weight of 1-methyl-2-ethynylbenzene, 0 to 15% by weight of 1-methyl-2-ethynylbenzene, and at least 85% by weight of 1-methyl-4-ethynylbenzene (hereinafter P A polymer composition (hereinafter referred to as "PMS polymer composition") containing a polymer (hereinafter referred to as "PMS polymer") whose polymer constituent is an isomer mixture (hereinafter referred to as "FMS mixture") of (abbreviated as “thing”)
As disclosed in JP-A-54-112989, for example, compared to a polymer composition containing a polymer containing styrene as a polymer constituent, it has a higher softening temperature and better fluidity during molding. It is known that it has characteristics such as being easily flame retardant. However, when processing such PMS-based polymer compositions, a strange odor is generated, and during long processing operations, there is a problem in that it inflicts divine pain on workers and those around the workplace. It has occurred. Such beard odor does not occur in styrene polymers, but P
This occurs significantly during the molding process of MS-based polymer compositions, and is a major disadvantage in the molding process.

In view of the seriousness of this problem, the inventors of the present invention have conducted extensive studies, and have surprisingly found that by adjusting the amount of 1-methyl-4-ethynylbenzene present in the FMS system bogie combination composition, such off-odor can be eliminated. The present invention was achieved by discovering that this can reduce the risk of damage.

That is, the present invention deals with
ethynylbenzene and at least 85ii% t7), 1
- A polymer composition comprising a polymer having an isomer mixture of methyl-4-ethynylbenzene as a polymer constituent,
The amount of 1-methyl-4-ethynylbenzene remaining in the polymer composition can be reduced from 0.3 to 0.0 without using reprecipitation drying method.
This is a polymer composition characterized in that it is adjusted to have a length of 3 m.

The 5FMS mixture used in the present invention is, for example, JP-A-53-1
A mixture comprising 0 to 01% by weight of 1-methyl-2-ethynylbenzene, 0 to 15% by weight of methyl-6-ethynylbenzene and at least 85% by weight of 1-methyl-4-ethynylbenzene as disclosed in US Pat. It is.

The 5FMS polymer used in the present invention is, for example, JP-A-54-1
45784, etc., and includes, for example, a polymer of the PMS mixture itself, and a copolymer of a PMS mixture and a monomer copolymerizable with the PMS mixture. Types of copolymers include random copolymers, block copolymers, graft copolymers, and the like. As copolymerizable monomers, monomers used in ordinary styrene copolymerization are advantageously used, such as styrene flame, acrylonitrile, methyl methacrylates, butadienes, ethylenes, propylenes, anhydrous One or more types of maleic acids and the like are used. Also included are impact copolymers comprising FMS mixtures and/or PMS mixtures grafted onto rubbery polymers and one or more other monomers.

In the known polymers containing styrene as a polymer constituent, polymers in which part or all of the styrene is replaced with a PMS mixture are also included in the polymers containing a PMS mixture as a polymer constituent in the present invention. In the present invention, the PM8 polymer composition is P5 in the present invention.
MS-based polymers include known styrene-based polymers.

In addition, the PMS polymer referred to in the present invention may include other known resins,
Also included are compositions blended with III compositions, such as polycarbonates, polyphenylene ethers, rubbery polymers, polystyrene, anti-ballast polystyrene foams, and the like. Among these, a mixture of a PMS-based Eastoglycan modified with a rubber-like polymer and a polyphenylene ether-based polymer is particularly preferably used.

In the present invention (・5), in the FMS-based polymer composition, the amount of 1-methyl-4-ethynylbenzene remaining in the polymer composition is 0.3 to 0.06% by weight, preferably 0.2 to 0.06% by weight of the weight of the polymer composition. ~0.06 weight ratio, sometimes preferred L < is 0.
It should be between 1 and 006% by weight, more preferably between 007 and 006%. The amount of 1-methyl-4-ethynylbenzene in such polymer compositions is determined by gas chromatography.

The conditions of the gas chromatography method are not particularly limited, but for example, as a column packing material, conditions are used in which a polyethylene glycol 201V column manufactured by Nishio Kogyo Co., Ltd. has a length of m and a temperature of 150°C.

The analytical procedure is similar to that of placing a meter of styrene remaining in a styrene polymer, but dimethylformamide, which is an analytical solvent usually used for styrene, is
-Methyl-'-ethynylbenzene and its peak overlap, so it is not used.

Methyl ethyl ketone is preferably used as the analytical solvent. Moreover, as a quantitative method, an internal standard method is preferably used.

1-methyl- remaining in the PMS polymer composition (
When the amount of 4-ethynylbenzene exceeds 0.6% by weight, the off-odor during processing becomes extremely large, and even when the amount exceeds 0.2% by weight, there is a considerable off-odor. The amount of styrene remaining in commercially available styrene polymer compositions is usually 0.8% by weight or less, but even when the weight range exceeds 0.3%, there is almost no off-odor, and even if the amount of remaining styrene is reduced, Since no improvement effect on odor was found, the above-mentioned off-odor is unique to PMS-based polymer compositions. Such off-odor becomes stronger when the temperature of the composition during processing is 2000C or higher, and therefore the off-odor reduction effect of the present invention is 26.
This is noticeable in resin molded objects that are subjected to processing conditions of 0°C or higher.

In the present invention, the amount of residual 1-f-/l/-4-ethynylbenzene in the PMS polymer composition can be adjusted by those skilled in the art. method, but requires more severe conditions than those for controlling residual styrene in styrenic polymer compositions.

That is, the amount of remaining 1-methyl-4-ethynylbenzene is
Amount of polymerization initiator used during polymerization - Adjustment of polymerization conversion rate by polymerization temperature, etc., steam stripping as a monomer removal step after polymerization, devolatilization step in continuous polymerization method, polymer extrusion step, etc. It can be carried out in one step or in a combination of these steps. In such a process, the amount of residual 1-methyl-4-ethynylbenzene in the FMS polymer composition is controlled, for example, by one polymerization initiator, compared to the control of the residual styrene in the styrenic polymer composition. In the continuous polymerization process, increasing the temperature in the devolatilization process, increasing the degree of vacuum, adding large amounts of inert ingredients such as water, and in the extrusion process. It is necessary to raise the temperature, improve the degree of vacuum in the vent section, and add a large amount of inert ingredients such as water.

The composition of the present invention does not require reprecipitation or drying (FM
The amount of 1-methyl-4-ethynylbenzene remaining in the S-based polymer silk acid is adjusted to a polymerization ratio of 0.3 to O, O3. The re-precipitation drying method involves re-precipitating the PMS-based polymer after polymerization in a PMS-based polymer non-solvent such as methanol, separating the precipitate by filtration or centrifugation, and then drying. This refers to a method for separating harmful substances and/or solvents from PMS polymers. Polymer compositions obtained by the darning method have great disadvantages in industrial processing, such as poor fluidity during processing and requiring an increase in processing temperature. In addition, the reprecipitation/drying process requires extremely complicated steps compared to the above-mentioned volatile matter removal process, so it is economically disadvantageous and unsuitable for industrial production.

In addition, when reducing the amount of residual 1-methyl-4-ethynylbenzene in the composition of the present invention to less than 00606 weight,
Since it is exposed to harsher conditions than the styrene polymer composition, under conditions where it is reduced to less than 0.06 parts by weight, the FMS polymer composition is caused by gelation, crosslinking decomposition, etc. of the resin that is thought to be caused by the PMS polymer. There is a significant decrease in one or more of the properties of the product, such as hue, transparency, mechanical strength, etc., and the performance of the molded product processed and manufactured is significantly impaired.
In addition, in the composition of the present invention, which requires a large amount of cost and is disadvantageous from the economic point of view of industrial production, the 18,000 heat volatilization softening of the polymer composition is 0.15 weight coefficient or less. 0.10% by weight
It is preferable that it is below. The 18,000 heating volatilization loss in this case is measured as follows. That is, the sample has a diameter of 1
Spread about 10 Jr. of granules with a length of ~5 mg and a length of 2 to 7 urns in a glass petri dish, and add 1
After heating for 90 minutes at 05°0.

Weigh accurately, then heat at 180°C for 9o, weigh accurately, 1
The amount of weight loss after heating at 05°C is determined and is defined as the weight loss on heating. Regarding the relationship between the 180°C heating loss meter (heating loss) and the amount of residual 1-Mef-4-ethynylbenzene (residual amount), the residual amount usually tends to decrease with heating loss, but for example, PMS When the types of volatile components contained in the system composition are different, there is often a difference in the residual amount even if the loss on heating is the same.

The PMS polymer composition of the present invention can be produced by, for example, injection molding,
Extrusion molding method, vacuum molding method, foam molding method, press molding method,
It is processed by known resin processing methods such as casting moldability, and is finally put into practical use as a molded product.

The PMS polymer composition of the present invention significantly reduces the occurrence of off-odor during processing, particularly during processing at high temperatures, and has a significant effect on improving the safety and health of the working environment.

Next, the present invention will be specifically explained using Examples and Comparative Examples.

Examples 1 to 3 and Comparative Example 1 a. Production of PMS-based polymer silk acid product IOO weight parts of a PM8 mixture (manufactured by Mobil Oil Co., Ltd.) were continuously supplied to a stirred tank reactor, and the average residence time was 4 hours.
A polymerization mixture was obtained at a polymerization temperature of 160°C, and then extruded through a devolatilization step consisting of a preheater and a vacuum tank connected in series with the reactor, and then granulated to obtain an FM8 polymer composition. Ta. The temperature of the preheater is 260°C and the vacuum degree of the vacuum chamber is 8.
PMS polymer compositions having different amounts of residual 1-methyl-4-ethynylbenzene shown in Table 1 were obtained by successively reducing the amount of 1-methyl-4-ethynylbenzene listed in Table 1. The composition of the PMS mixture used was 97% 1-
Methyl-4-ethynylbenzene and filter filter 1-methyl-
6-ethynylbenzenetheal.

b. Evaluation of off-odor The obtained polymer composition was heated in a cylinder at a temperature of 240°C.
An extruder with a screw diameter of 50 fLm was used to continuously extrude a sheet with a width of 350 mm and a thickness of 1.5 mm, and during the extrusion process, 5 people measured the intensity of the off-odor at a position 1 mσ from the die exit of the extruder. was judged by sensation. The evaluation criteria are as follows.

5 points: Strong strange odor. 2 points: Fabric with a strange odor. 1 point: Slightly abnormal odor. 0
Point: No strange odor.

The evaluation scores of five people are totaled, and the value indicates the off-odor intensity of the polymer composition.

The results are listed in Table 1.

Reference Example 1 Polymerization evaluation was carried out in the same manner as in Example 1 except that the raw material supplied to the reactor was changed to styrene.

The results are listed in Table 1.

Comparative Example 2 In order to obtain a 1'MS polymer composition with a lower amount of residual 1-methyl-4-ethynylbenzene than in Example 3, the temperature of the preheater was adjusted to 295° in Example B, resulting in one resin composition. Small irregularities are formed on the surface of the object, and when molded, the transparency is extremely low/- Bottom 1. Therefore, the experiment was discontinued.

Example 4 and Comparative Example 6 The polymer compositions produced in Example 1 and Comparative Example 1 were tested at a temperature of 210° 0 for the evaluation of b in Example 1.

Example 5 and Comparative Example 4 a. Production of PMS polymer composition In a stirred tank reactor, 75 parts by weight of a PMS mixture (manufactured by Mobil Oil) and 25 parts by weight of acrylonitrile were added 1 part by weight of ethylbenzene and 1 part by weight of ethylbenzene. A raw material liquid consisting of 02 parts by weight of dodecyl mercaptan is supplied, and the average residence time is 1.
A polymerization mixture was obtained at a polymerization temperature of 145°C, and then passed through a devolatilization process consisting of a preheater and a vacuum chamber connected in series with the reactor, passed through an extruder, and then granulated to form an FMS polymer. A composition was obtained. The temperature of the preheater was set at 280° C., and the degree of vacuum of the vacuum chamber was controlled to obtain PMS polymer compositions having different residual 1-methyl-4-ethynylbenzene acid as shown in Table 6.

b. Evaluation of off-odor The obtained polymer composition was injected at 100% r mold clamping pressure 75
A molded product with a weight of 75 ir and a surface area of 96 cnt was continuously molded using an injection molding machine at a temperature of 250 ° 0 for 50 seconds/1 shot. The measurer visually judged the intensity of the off-odor. The evaluation criteria are as follows.

6 points: Strong strange odor. 2 points: abnormality. 1 point: Slight odor, 0
Point: No strange odor.

The evaluation scores of five people are totaled, and the value indicates the off-odor intensity of the polymer composition.

The results are recorded in Table 5.

Table 6 Example 6.7 In Comparative Example 1, PMS mixture (manufactured by Mobil Oil Co., Ltd.) was added to the raw material to be supplied to the reactor, and 760 parts by weight of PMS mixture (manufactured by Mobil Oil Co., Ltd.) was added to the raw material. An S-based polymer composition was produced. Manufactured in Example 1 1. It was evaluated by the method of Example 5 in comparison with the FMS polymer composition (Example 7).

The results are shown in Table 4.

Table 4 Example 8 A raw material liquid consisting of 95 parts by weight of FMS-based mixture, 5 parts by weight of polybutadiene, and 10 parts by weight of ethylbenzene was continuously supplied to a 6-stage stirred tank array type reactor, and the degree of vacuum was 5 Q 1e.
A rubber-modified PMS mixture polymer was obtained after passing through a vacuum chamber under the conditions of rc and performing an operation for removing volatile matter. 60 parts of the rubber-modified pMs mixture polymer and 40 parts of polyphenylene ether were heated at a vent vacuum degree of σ4-tz and an extrusion temperature of 240°.
The mixture was mixed using a C extruder.

Table 5 shows the results of the same evaluation as in Example 5.

Comparative Example 5 Example 8 except that the degree of vacuum when obtaining the rubber-modified FMS mixture polymer was set to 13 Q i6a, 4, the vent vacuum of the extruder was set to 50, and the extrusion temperature was set to 230"O. Evaluation was made in the same manner as in 8.

The results are shown in Table 5.

Table 5 Patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1) 0 to 0.1% by weight of 1-methyl-2-ethynylbenzene, 0 to 15% by weight of 1-methyl-6-ethynylbenzene and at least 85ii% of 1-methylbenzene. In a polymer composition containing a polymer having an isomer mixture of methylethynylbenzene consisting of methyl-4-ethynylbenzene as a polymer constituent, 1-methyl-
A polymer composition characterized in that the amount of 4-ethynylbenzene is adjusted to 0.5 to 0.03 times by using a reprecipitation drying method. 2) The volatilization loss on heating at 180°C of the polymer composition is 0.15.
The polymer composition according to claim 1, which has a weight of less than 100 kg. 3) The amount of 1-methyl-4-ethynylbenzene in the polymer composition is 01 to 0.05% by weight.
The polymer composition according to Items 1 and 2.