JPH0113486B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel 4-methyl-1-pentene copolymer. Crystalline 4-methyl-1-pentene homopolymer or 4-methyl-1-pentene and other α-
Copolymers with olefins are generally produced by stereospecific catalysts using titanium catalyst components such as titanium trichloride. 4- produced with this catalyst
Methyl-1-pentene homopolymers or copolymers are insoluble in many solvents at room temperature, and therefore must be subject to many restrictions when used as solution-type paints or adhesives. The homopolymer or copolymer has a wide molecular weight distribution and a high melting point. For example, the ratio of weight average molecular weight to number average molecular weight (hereinafter referred to as molecular weight distribution) is often a value of 6 or more. Also, the melting point Tm when the polymerized unit of 4-methyl-1-pentene is x% by weight
(°C) is not significantly different from the value of 3x−60. It is known to make products with lower molecular weights by kneading the above-mentioned homopolymers or copolymers using an extruder, etc., but according to the general method, the molecular structure is essentially the same as that of the raw material. It does not change, and its melting point and solubility hardly change unless the molecular weight becomes extremely small. Further, in a method using such an extruder, a method in which the extrusion is carried out in the presence of a small amount of a radical initiator is disclosed in US Pat. No. 3,144,436. This specification clearly states that the polymer obtained by decomposition has the same solubility as the base polymer, and in the example of decomposition of 4-methyl-1-pentene polymer, the melt index There are only examples where the amount is about 20 to 25 times higher. In fact, it can be said that at this level of decomposition, there is almost no difference in molecular structure, melting point, solubility, etc. between the raw material and the decomposition product. The present inventors were at the stage of researching the modification of a polymer or copolymer of 4-methyl-1-pentene, using a radical initiator to change the molecular structure of the polymer or copolymer. It has been found that when the decomposition is carried out, copolymers with improved properties are obtained. This copolymer consists of (A) a 4-methyl-1-pentene polymer unit and at least one unsaturated hydrocarbon polymer unit having 2 to 18 carbon atoms (excluding 4-methyl-1-pentene); - a methyl-1-pentene random copolymer, wherein (B) the 4-methyl-1-pentene polymerized unit is in the range of 70 to 99.7% by weight and the unsaturated hydrocarbon polymerized unit is in the range of 0.3 to 30% by weight; Yes, (C) melting point based on differential scanning calorimetry of 100 to 235
℃ range and when the polymerized unit of 4-methyl-1-pentene is x% by weight, the melting point is (5x-
260)℃ or less (if x≧95) or (3x−70)
(D) The intrinsic viscosity measured in decalin at 135°C is 0.2
10.0 dl/g, (E) Weight average molecular weight/number average molecular weight 1.5 or more
Characterized by 3.8. The copolymer of the present invention contains 70 to 99.7% by weight of 4-methyl-1-pentene polymerized units, preferably
80 to 99.5% by weight, and 0.3 to 30% by weight, preferably 0.5 to 20% by weight of polymerized units of other unsaturated hydrocarbons. As will be explained later, the copolymer of the present invention does not refer only to a direct copolymer of 4-methyl-1-pentene and other unsaturated hydrocarbons, but also to a copolymer of 4-methyl-1-pentene. When a homopolymer or copolymer is decomposed and new unsaturated hydrocarbon copolymer units are generated, it is considered to be a copolymer of such unsaturated hydrocarbons. Examples of polymerized units of unsaturated hydrocarbons having 2 to 18 carbon atoms other than 4-methyl-1-pentene include ethylene, propylene, 1-butene, isobutene,
-Pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 3-methyl-1
-Pentene, 2-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-
Octadecene, vinylcyclohexane, styrene, allylbenzene, α-methylstyrene, β
- Polymerized units such as methylstyrene, vinyltoluene, vinylethylbenzene, vinylcumene, etc. may be mentioned. These polymerized units may be generated by direct copolymerization, or may be generated by cutting off a portion of the originally existing polymerized units during decomposition, or When a radical initiator, a solvent, or the like is used, it may be generated by adding a decomposition product of the radical initiator or a solvent. These 4-methyl-1
-Polymerized units of unsaturated hydrocarbons other than pentene are 2
There may be more than one species. Also, if the amount is small,
Oxygenated vinyl monomer units with attached peroxide fragments, such as units such as vinyl phenyl ketone and vinyl phenyl carbinol, may also be present. Note that the polymerized unit of 4-methyl-1-pentene in the copolymer of the present invention can be determined by infrared absorption spectrum. For example, the infrared absorption spectra of a solution of the copolymer according to the present invention in a suitable solvent and a solution of 4-methyl-1-pentene homopolymer are taken, and the 1365 cm
The content of 4-methyl-1-pentene polymer units in the copolymer can be determined from the ratio of the absorbance of the maximum absorption band around ^-1 . Differential scanning calorimetry (DSC) of the copolymer of the present invention
The melting point based on
95) or below (3x-70)°C (when x<95). Note that the melting point here is measured as follows. That is, the sample is subjected to differential scanning calorimetry (du
Pout990 type), the temperature was raised from room temperature at a rate of 20℃/min, and when it reached 250℃, the temperature was lowered at a rate of 20℃/min, once lowered to 25℃, and then again at a rate of 20℃/min.
The temperature is increased at a rate of min, and the melting point is read from the melting peak at this time (in many cases, multiple melting peaks appear, so in this case, the value on the higher melting point side was used). Based on this measurement method, the melting point of a normal homopolymer of 4-methyl-1-pentene obtained by polymerization using a stereospecific catalyst is around 240°C, and The pentene copolymer has a 4-methyl-1-pentene content of x% by weight.
%, many have melting points around (3x-60)°C. Therefore, when compared with a 4-methyl-1-pentene copolymer obtained using such a stereospecific catalyst, the copolymer of the present invention has the same 4-methyl-1-pentene polymer units. Comparing the contents, it can be said that the melting point is considerably low. In order for the copolymer of the present invention to be useful as films, paints, adhesives, and various other molded products,
Intrinsic viscosity [η] measured in decalin at 135℃ is 0.2
to 10.0dl/g, preferably 0.4 to 5.0dl/
It is g. The copolymer of the present invention has a narrow molecular weight distribution and a weight average molecular weight/number average molecular weight (Mw/Mn) of 1.5 to 3.8, preferably 1.7 to 3.0. Here
Mw/Mn is determined by gel vermiaction chromatography (GPC) as follows. That is, o-dichlorobenzene was used as a solvent, and 0.04 g of polymer was added to 100 parts by weight of the solvent.
(2,6-di-tert-butyl-p-
Add 0.05g of cresol per 100 parts by weight of the polymer to form a solution, and then pass through a 1μ filter to remove insoluble matter such as dust. after that,
GPC set at column temperature 135°C and flow rate 1.0ml/min
It was measured using a measuring device, and the numerical ratio was converted on a polystyrene basis. Such a copolymer with a narrow molecular weight distribution is preferable because it further improves solubility especially near room temperature. 4- produced using a general stereospecific catalyst
The methyl-1-pentene homopolymer or copolymer often has a Mw/Mn of more than 6. The copolymers of the present invention often have a crystallinity based on DSC in the range of 3 to 33%. The degree of crystallinity was measured by the following method. That is, using the chart for measuring the melting point by DSC described above, the melting area (S) of the measurement sample,
The melting area (So) on the recording paper corresponding to the melting energy (Po) per unit amount of indium, which is a control sample, is compared. Since the amount of Po in indium is known, and the melting energy (P) per unit amount of the crystal part of the 4-methyl-1-pentene polymer is also known as shown below, the crystallinity of the measurement sample is as follows. It is determined by the formula. Crystallinity (%) = S/So
Philosophical Magazine, 4 , 200 (1959)) In many cases, it has good solubility in solvents, and dissolves in cyclohexene at 25°C in an amount of 100 times or less by weight, preferably 30 times or less by weight. In this case, the copolymer was added to cyclohexene at 25°C, heated to 70°C at a rate of 25°C/hr, held at that temperature for 2 hours, and then heated again to 70°C at a rate of 25°C/hr.
A state in which the solution is completely transparent and no permeate is present when cooled to ℃ is considered to be a dissolved state. One method for obtaining the copolymer of the present invention is to prepare 4-methyl-1-pentene or 4-methyl-1-pentene and other α-C2 to C18 copolymers in the presence of a stereospecific catalyst. Examples include a method in which a 4-methyl-1-pentene polymer or copolymer obtained by polymerization or copolymerization with olefin is decomposed under specific conditions in the presence of an organic peroxide.
A 4-methyl-1-pentene homopolymer is suitable as such a raw material, and when a 4-methyl-1-pentene copolymer is used as a raw material, a 4-methyl-1-pentene homopolymer is suitable as a raw material.
It is preferable to use one having a methyl-1-pentene content of 85% by weight or more. A preferred method for decomposition is to prepare the 4-methyl-1-pentene polymer or copolymer in a hydrocarbon solvent in the presence of an organic peroxide under conditions such that the polymer or copolymer is dissolved. This method maintains the temperature between 100 and 400℃. Hydrocarbon solvents include hexane, heptane, octane, decane, dodecane, tetradecane, aliphatic hydrocarbons such as kerosene, alicyclic hydrocarbons such as methylcyclopentane, cyclohexane, methylcyclohexane, cyclooctane, cyclododecane, benzene, toluene, xylene,
Examples include aromatic hydrocarbons such as ethylbenzene, cumene, ethyltoluene, trimethylbenzene, cymene, and diisopropylenebenzene. Among these, alkyl aromatic hydrocarbons are particularly preferred. When such a solvent is used, the solvent is often added to the decomposition product, and the amount thereof is particularly large when an alkyl aromatic hydrocarbon is used. The amount of solvent used is based on 100 parts by weight of the raw material 4-methyl-1-pentene polymer or copolymer.
100 to 100,000 parts by weight, especially 300 to 10,000 parts by weight
Preferably, it is expressed in parts by weight. Typical organic peroxides used in the above method include alkyl peroxides, aryl peroxides, acyl peroxides, aroyl peroxides, ketone peroxides, peroxycarbonates, peroxycarboxylates,
There are hydroperoxides, etc. Examples of alkyl peroxides include diisopropyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di-tert-butylperoxyhexine-
Aryl peroxides include dicumyl peroxide, acyl peroxides include dilauroyl peroxide, aroyl peroxides include dibenzoyl peroxide, ketone peroxides include methyl ethyl ketone hydroperoxide and cyclohexanone peroxide, and hydroperoxides include ,
Examples include tert-butyl hydroperoxide and cumene hydroperoxide. Among these are di-tert-butyl peroxide, 2,
Preferred are 5-dimethyl-2,5-di-tert-butylperoxy-hexyne-3, dicumyl peroxide, dibenzoyl peroxide, and the like. The amount of organic peroxide used is 5 to 1000 parts by weight per 100 parts by weight of the raw material polymer or copolymer.
In particular, it is preferably 10 to 600 parts by weight.
The decomposition temperature is 100 to 250℃, especially 120 to 250℃.
The temperature range is preferably 200°C, and the appropriate decomposition time is about 10 minutes to 10 hours. The decomposition reaction can be carried out in a batch manner or in a continuous manner, and in the case of a batch method, a method of sequentially adding an organic peroxide and a raw material polymer or copolymer can be adopted. The degree of decomposition is determined by the intrinsic viscosity of the decomposition product [η]
is preferably 0.1 to 50%, particularly 1 to 20%, of the limiting viscosity [η] of the raw material. When employing such decomposition methods, the 4-methyl-1-pentene polymerized units are often reduced compared to the starting material. This is because not only the main chain of the raw material is cleaved, but also side chains are cleaved, and hydrocarbon groups are added based on the solvent and/or organic peroxide. Further, as a method for the decomposition reaction, a method can also be adopted in which the molecule is contacted in a molten state with a radical initiator consisting of a peroxide whose molecular chain has hydrocarbons at both ends using an extruder or the like. In this case, 0.7 parts of radical initiator is added to 100 parts by weight of raw material polymer.
It is sufficient to add from 1 to 10 parts by weight, preferably from 1.0 to 5 parts by weight, and knead at 200 to 400°C for 0.5 to 10 minutes. Furthermore, in the case of decomposition by this melt reaction, the efficiency of lowering the melting point varies depending on the type of radical initiator used. Therefore, in this case, among organic peroxides, alkyl peroxides, acyl peroxides, aroyl peroxides, ketone peroxides, peroxycarbonates, and peroxycarboxylates are preferable as the radical initiator. Particularly preferred are alkyl peroxides, which have a molecular weight of 200 or more, more preferably 250 or more, have no aromatic ring, and have two peroxide groups in one molecule. Specifically, such peroxides include 2,5-dimethyl-2,5
-di-tert-butylperoxy-hexane, 2,
Examples include 5-dimethyl-2,5-di-tert-butylperoxy-hexyne-3 and α,α'-di-tert-butylperoxydiisopropylbenzene. Furthermore, as a method for adding these peroxides to the polymer, it is preferable to mix them into a powder or pellet form of the polymer in advance. Although it is possible to inject the peroxide into the polymer melt through the cylinder of an extruder, in most cases it is necessary to dissolve the peroxide in a solvent, which poses a risk of ignition and explosion. The need for major changes in machine design (e.g. increasing the length from the injection zone to the die, thus increasing the screw L/D) and even the need to add peroxide to the polymer melt (solution ) is not dispersed within a short period of time, the polymer tends to partially decompose and the product tends to be non-uniform. The copolymer of the present invention has good solubility in various solvents, and therefore, solutions dissolved in such solvents can be used for various substrates, such as coatings for metals, polyolefins, glass, etc., adhesives, paints, etc. It can be used for. Suitable solvents used for this purpose include halogenated hydrocarbons such as carbon tetrachloride, trichloride, chloroform, and chlorobenzene, and hydrocarbons such as cyclohexane and cyclohexene. The copolymers of the present invention can also be used in conventional 4-methyl-1
- Like pentene polymers or copolymers, it can be used by forming into films, sheets, hollow bottles, tubes, and various molded products by extrusion molding, injection molding, blow molding, vacuum molding, etc. In these various uses, stabilizers, antioxidants, ultraviolet absorbers, pigments, dyes, various fillers, and the like can be blended as appropriate. The copolymer of the present invention can also be used as a modifier for other resins and rubbers by being blended with many resins and rubbers. For example, polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-
It can be used in a blend with pentene, ethylene/propylene copolymer, ethylene/1-butene copolymer, etc. It is also possible to improve the solvent paintability, adhesion, printability, etc. of various molded products such as films, sheets, tubes, pipes, and hollow bottles obtained from these compositions by conventional molding methods. Generally, similar effects are observed when amorphous copolymer rubbers are blended, but in this case, there are drawbacks such as a decrease in mechanical strength and hardness of the blended composition, but the copolymer of the present invention A blended composition does not have this drawback because it still has crystallinity. Example 1 Homopolymer of 4-methyl-1-pentene ([η]
9.38, melting point 237℃, molecular weight distribution 7.1, crystallinity 35
%) was added to toluene 1, the system was purged with nitrogen, and the temperature was raised to 145°C to completely dissolve the polymer. Later, dicumyl peroxide
32.4 g (dissolved in 100 ml of toluene) was fed to the system over 4 hours and stirring continued for an additional 2 hours. After the reaction mixture was cooled to room temperature, a large amount of acetone was added to completely precipitate the polymer, and the polymer was recovered. The wet cake was further washed repeatedly with acetone and dried under reduced pressure at 60°C to obtain a purified 4-methyl-1-pentene copolymer. The melting point of this reaction product was 216°C, [η] 1.12, molecular weight distribution 2.3, crystallinity 21%, and 4-methyl-1-
The composition had a pentene unit content of 99.2 wt%, an allylbenzene unit content of 0.4 wt%, a propylene unit content of 0.2 wt%, and a trace amount of vinyl phenyl ketone units. Reference Example 1 When 2 g of the 4-methyl-1-pentene copolymer obtained in Example 1 was dissolved in 100 ml of cyclohexane at 70°C and cooled to room temperature, the polymer did not precipitate or precipitate at all, and a completely uniform mixture was formed. It was a clear solution. Reference Example 2 When the solution of the polymer obtained in Reference Example 1 was applied on an aluminum plate at room temperature, a uniform and transparent thin film was formed simply by air drying at room temperature. Examples 2 to 10 4-Methyl-1
-A pentene copolymer was synthesized. Table 1 shows the physical properties and composition of the purified polymer. In addition, the solubility at room temperature and the film formability at room temperature of these 4-methyl-1-pentene copolymers were investigated in exactly the same manner as in Reference Examples 1 and 2. The results are shown in Table 1.

[Table] Comparative Example 2 [η] 3.6 according to the method described in USP-3144436
4-methyl-1-pentene homopolymer (melting point
238℃, crystallinity 36%, molecular weight distribution 7.2) 0.08 tert-butyl hydroperoxide per 100 parts by weight
20 minutes at 300℃ after mixing well.
Decomposition was carried out using a mmφ extruder (screw L/D=28). Table 2 shows the physical properties of the obtained polymer. Further, according to the methods of Reference Examples 1 and 2, the room temperature solubility in cyclohexane and the room temperature film formability were investigated, and Table 2 shows the results. Comparative Examples 3 and 4 A copolymer of 4-methyl-1-pentene and 1-decene was synthesized using a common titanium-based catalyst. These physical properties are shown in Table 2. Table 2 also shows the room temperature solubility and room temperature film formability of these copolymers. Comparative Example 5 A 4-methyl-1-pentene homopolymer with [η] 1.34 (melting point 237°C, molecular weight distribution 6.9, crystallinity 36%) obtained by a polymerization method was treated with trichlene as a good solvent and as a poor solvent. It was fractionated into six fractions with different molecular weights by a conventional fractionation method using methanol as a solvent. Table 2 shows the physical properties and compositions of each of these fractions and raw material polymers. Further, according to the methods of Reference Examples 1 and 2, the solubility in cyclohexene at room temperature and the room temperature film forming properties of the solution were also investigated. The results are shown in Table 2, and none of the fractions was completely soluble in cyclohexene at room temperature. In addition, Fraction No. 1 to No. 3 have lower melting points than the raw material polymer, but this is simply an effect of lowering the molecular weight, and properties such as room temperature solubility are lower than the raw material weight. It is clear that nothing has changed since the merger. Furthermore, although the molecular weight distribution of these fractions has become narrower due to fractionation, it is clear that in this case as well, simply narrowing the molecular weight distribution does not cause changes in properties such as room temperature solubility. From now on, this completely new property is produced by modifying the 4-methyl-1-pentene (co)polymer to change its molecular structure (1) reduction of 4-methyl-1-pentene units and new polymerized units. (2) the melting point is lowered to an extent unimaginable in normal copolymerization despite the relatively low comonomer content, and (3) this is caused by a narrowing of the molecular weight distribution. is clear.

[Table] ×: No dissolution at all Examples 11 to 14 The reaction was carried out in the same manner as in Example 1, except that the reaction solvent listed in Table 3 was used and the reaction was carried out at the temperature shown in Table 3. . The obtained 4-methyl-1
Table 3 shows the physical properties of the -pentene copolymer, as well as the results of room temperature solubility and room temperature film formability conducted in the same manner as in Reference Examples 1 and 2. Examples 15 to 19 4-methyl-1-pentene copolymers were synthesized in the same manner as in Example 1, except that the organic peroxides shown in Table 4 were used. The physical properties of the obtained polymer are shown in the table. Further, Table 4 shows the results of room temperature solubility and room temperature film formability.

【table】

[Table] Examples 20 to 27 Various 4-methyl-1- A pentene copolymer was synthesized. These physical properties are shown in Table 5. In addition, room temperature solubility and room temperature film formability were examined in the same manner as in Reference Examples 1 and 2. The results are shown in Table 5.

[Table] Example 28 To 100 parts by weight of the 4-methyl-1-pentene homopolymer used in Example 1, 2,5-dimethyl2,
5-di-tert-butylperoxide-hexyne-
3. Add 1 part by weight and mix well, then transfer to a 20 mmφ extruder (L/D) set at 290°C under nitrogen atmosphere.
=28). The obtained polymer had a [η] of 0.70, a melting point of 220°C, a molecular weight distribution of 2.0, a crystallinity of 24%, and a content of 4-methyl-1-pentene units of 99.1% by weight. Further, when the solubility of this product at room temperature was examined according to Reference Example 1, a clear solution was obtained.

Claims (1)

[Claims] 1 (A) 4-methyl-1-pentene polymerized unit;
A 4-methyl-1-pentene random copolymer consisting of at least one unsaturated hydrocarbon (excluding 4-methyl-1-pentene) polymerized unit having 2 to 18 carbon atoms, (B) 4-methyl -1-pentene polymerized units range from 70 to 99.7% by weight and said unsaturated hydrocarbon polymerized units range from 0.3 to 30% by weight; (C) a melting point based on differential scanning calorimetry of 100 to 235;
℃ range and when the polymerized unit of 4-methyl-1-pentene is x% by weight, the melting point is (5x-
260)℃ or less (if x≧95) or (3x−70)
(D) The intrinsic viscosity measured in decalin at 135°C is 0.2
10.0 dl/g, (E) Weight average molecular weight/number average molecular weight 1.5 or more
3.8 A 4-methyl-1-pentene copolymer characterized by: