JPH0931300A - Waterproof sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a waterproof sheet which excels in flexiblity, tear strength and cold resistance, has good resistance to thermofusibility and lightweightness, and is useful for civil engineering and architectural work and motor vehicles. SOLUTION: This waterproof sheet comprises a propylene-α-olefin block copolymer that has primary crystallization peak temperature of 85-95 deg.C, half- value width of the primary crystallization peak temperature within the range of 3-10 deg.C, secondary crystallization peak temperature of 65-75 deg.C, and the ratio of the secondary crystallization peak area to the primary crystallization peak area within the range of 3-15% in the crystallization temperature curve determined by differential scanning calorimetry. The above copolymer contains 30-70wt.% P.P blocks and 70-30wt.% of copolymer blocks of propylene with other α-olefins.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof sheet which is excellent in flexibility, tear strength and cold resistance, and which has good heat-sealing property (leaster processability) and light weight.

[0002]

2. Description of the Related Art Conventionally, soft vinyl chloride resin has been widely used as a waterproof sheet. However, since the so-called PVC sheet usually contains a large amount of plasticizer, if it is used for a long period of time, it causes contamination due to bleed-out of the plasticizer or causes weather resistance, cold resistance deterioration, and poor heat fusion resistance. was there. In addition, there is concern about the generation of toxic gas during waste treatment, which causes environmental problems. So, in recent years,
As a substitute for this, a waterproof sheet using a polyolefin-based elastomer has been proposed (for example, JP-A-2-255733, JP-A-4-185652, JP-A-5-9307, etc.).

[0003]

However, all of these waterproof sheets are still insufficient in flexibility, tear strength and puncture strength, and the sheet containing EPDM is poor in heat fusion property and crosslinked. There was also a problem that the type was inferior in recyclability. The present invention has been made in view of such circumstances, flexibility, tear strength, excellent in cold resistance,
Another object of the present invention is to provide a waterproof sheet having a good heat fusion property.

[0004]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the above object can be achieved by a propylene-α-olefin block copolymer having specific physical properties. Based on this, the present invention has been completed. That is, the present invention provides a waterproof sheet made of a propylene-α-olefin block copolymer having the following physical properties. In a crystallization temperature curve measured using a differential scanning calorimeter, (A) main crystallization peak temperature: 85 to 95 ° C (B) main crystallization peak temperature half-value width: 3 to 10 ° C (C) secondary Crystallization peak temperature: 65 to 75 ° C. (D) Ratio of secondary crystallization peak area to main crystallization peak area: 3 to 15% The present invention will be specifically described below.

The propylene-α-olefin block copolymer (hereinafter referred to as "BPP") in the present invention comprises a polypropylene block and a copolymer block of propylene and another α-olefin. Examples of the polypropylene block include homopolypropylene or a random copolymer of propylene and another α-olefin (the α-olefin copolymerization ratio is less than 5 mol%). On the other hand, examples of the copolymer block with α-olefin include a random copolymer of propylene and another α-olefin (the α-olefin copolymerization ratio is 5 mol% or more). The content of the α-olefin in the copolymer block is usually 30 to 70 mol%, preferably 32 to 68 mol%, and particularly preferably 35 to 65 mol%.

Other α-olefins mentioned above include those having 2 to 12 carbon atoms (excluding 3), and specific examples thereof include 1-butene, 3-methyl-1-butene,
3-methyl-1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, vinylcyclopentane, vinylcyclohexane and the like can be mentioned. These α-olefins may be used alone or in combination of two or more. Further, the proportion of the copolymer block in BPP is preferably 30 to 70% by weight, and particularly preferably 40 to 68% by weight.

Further, the BPP of the present invention is required to have the following physical properties. In a crystallization temperature curve measured using a differential scanning calorimeter, (A) main crystallization peak temperature: 85 to 95 ° C (B) main crystallization peak temperature half-value width: 3 to 10 ° C (C) secondary Crystallization peak temperature: 65 to 75 ° C. (D) Ratio of secondary crystallization peak area to main crystallization peak area: 3 to 15%

A crystallization temperature curve measured using a differential scanning calorimeter was obtained by heating BPP to 230 ° C., holding it for 5 minutes, and then cooling it to −30 ° C. at a temperature lowering rate of 20 ° C./min. It is what is done. An example of the crystallization temperature curve of BPP of the present invention is shown in FIG. The main crystallization peak temperature (hereinafter referred to as “Tcp1”) is 85 to 95 ° C. and 88 to 9
4 degreeC is preferable and 89-93 degreeC is especially suitable. Tc
If p1 is less than 85 ° C, the moldability is poor. On the other hand, if the temperature exceeds 95 ° C, the flexibility and the cold resistance are deteriorated, which is not preferable. T
The full width at half maximum of cp1 (hereinafter referred to as "δ") is the peak width at a position corresponding to 50% of the height of Tcp1,
The value is 3 to 10 ° C, preferably 3.5 to 8 ° C,
Particularly, 4 to 7 ° C is suitable. When δ is less than 3 ° C, flexibility and impact resistance are poor. On the other hand, if it exceeds 10 ° C, the transparency and moldability are poor.

The secondary crystallization peak temperature (hereinafter referred to as "Tc
p2 ") is 65 to 75 ° C, preferably 67 to 73 ° C, and particularly preferably 68 to 72 ° C. Tcp2 is 6
If it is less than 5 ° C, the moldability is poor. On the other hand, if it exceeds 75 ° C or does not have Tcp2 at all, the elongation at low temperature is insufficient, which hinders use in cold regions. The ratio of the secondary crystallization peak area to the main crystallization peak area is 3 to 15%,
4 to 13% is preferable, and 5 to 11% is particularly preferable.
If the ratio of the peak area is less than 3%, the moldability, rigidity and cold resistance are poor. On the other hand, if it exceeds 15%, the flexibility is deteriorated, which is not preferable.

Further, in the BPP of the present invention, it is preferable that the eluted components measured by cross fractionation chromatography have the following proportions. (I) Elution amount below 0 ° C: 50 to 65% by weight (ii) Elution amount above 0 ° C and 90 ° C: 10 to 28% by weight (iii) Outflow amount above 90 ° C and 130 ° C: 15 to 25% by weight

The cross fractionation chromatograph is called a temperature rising fractionation device.
e Rising Elution Fractionation Chromatography) to sort by comonomer and stereoregularity, then GP online
C is measured, and a three-dimensional structure distribution of elution temperature-molecular weight-component amount is obtained. For this device, see TAKAO USAMI et al; Jounal of Applied Polyner Sc
ience Applied Polymer Symposium Vol.52, pp145-158 (1
993) or JP-A-7-40519. The elution ratio by this cross fractionation chromatograph is
(I) The elution amount at 0 ° C or lower is preferably 50 to 65% by weight, and particularly preferably 55 to 60% by weight. (Ii) 0
The elution amount above 90 ° C and 90 ° C is preferably 10 to 28% by weight, and particularly preferably 15 to 25% by weight. (Iii) The elution amount at more than 90 ° C and 130 ° C is preferably 15 to 25% by weight, and particularly preferably 17 to 22% by weight.

Further, the BPP of the present invention preferably has the following physical properties. (1) Para-xylene insoluble matter at a temperature of 25 ° C .: 25 to
65% by weight (2) For the para-xylene solubles, (a) the average propylene content (F
P): 20 to 80 mol% (b) the propylene content of the high propylene content side by two-site model _(P P): ratio of 60 to 90 mol% (c) P _H occupied in the copolymer (P _f1): 0.4
0-0.90

The para-xylene insoluble matter is contained in the BPP at a temperature of 13
It represents a ratio of about 1% by weight dissolved in para-xylene at 0 ° C. and then precipitated when cooled to 25 ° C. In the present invention, 25 to 65% by weight is preferable, and 30 to 6 is particularly preferable.
0% by weight is preferred. On the other hand, the analysis result by the two-site model is important for the para-xylene solubles.

Here, this method will be described for the two-site model, taking the case of a propylene-ethylene copolymer as an example. FIG. 2 is a ¹³ C-NMR spectrum of a typical propylene-ethylene copolymer, and the spectrum gives 10 different peaks due to the difference in the chain distribution (arrangement of ethylene and propylene). The name of this chain is Carman, C,
J, Horrington, R, A, Wilkes, C, E; Macromolecules, Vol.1
0, p536-544 (1977) and is named as in FIG. Such a chain can be expressed as a reaction probability (P), assuming a reaction mechanism of copolymerization, and thus the relative intensities of the peaks of (1) to (10) when the overall peak intensity is 1. It can be expressed as a probability equation by Bernoulli statistics with P as a parameter.

For example, in the case of (1) Sαα, if the propylene unit is the symbol p and the ethylene unit is the symbol e, the possible chains are [pppp], [ppee], and [epp].
e], which are represented by reaction probabilities and are added together. The remaining peaks (2) to (10) can be obtained by formulating equations in the same manner, and optimizing P so that the peak intensity actually measured and those 10 equations are closest to each other. . The two-site model is a model that assumes this reaction mechanism. HNCHENG; Jounalof
Applied Polymer Sience, Vol.35 p1639-1650 (1988)
The definition is given in. That is, in a model in which propylene and ethylene are copolymerized using a heterogeneous catalyst, the propylene content (P _P ) of the copolymer (P _H ) generated at the active site that preferentially polymerizes propylene and ethylene are preferentially polymerized. Assuming that the propylene content (P ′ _P ) of the copolymer formed at the active sites that polymerize into the polymer is the parameter and the ratio of P _H to the copolymer (P _f1 ) is a parameter, the following Table 1
The probability equation shown in is obtained.

[0016]

[Table 1]

Therefore, by optimizing the three parameters P _P , P ′ _P and P _f1 so that the relative intensity of the ¹³ C-NMR spectrum described above and the probability equation shown in Table 1 match. ,Desired. The (a) average propylene content (FP) in the BPP of the present invention is determined by the following equation using the above three parameters. FP = P _P × P _f1 + P ′ _p × (1-P _f1 ) FP is preferably 20 to 80 mol%, further 30 to 70
Molar% is preferred. (b) P _P is preferably 60 to 90 mol%, and more preferably 65 to 85 mol%.
(C) P _f1 is preferably 0.40 to 0.90, more preferably 0.48 to 0.82.

The polymerization of BPP of the present invention is carried out by a slurry method in the presence of a liquefied α-olefin solvent such as hexane, heptane, kerosene, or an inert hydrocarbon or propylene, or a vapor phase polymerization method without a solvent. The temperature is in the range of room temperature to 130 ° C. Preferably, it is performed in the range of 50 to 90 ° C. The polymerization pressure is in the range of ^{2 to} 50 Kg / cm ² . As the reactor in the polymerization step, a reactor generally used in this technical field can be appropriately used. For example, a stirred tank reactor, a fluidized bed reactor, a continuous reactor using a circulation reactor,
It can be performed by either a semi-batch method or a batch method. Specifically, it is obtained by using a known multi-stage polymerization method.
That is, after polymerizing the first stage reactor propylene and / or propylene-α-olefin copolymer,
This is a method of copolymerizing propylene and α-olefins in a step reaction, for example, JP-A-2-258854, JP-A-3-97747, and JP-A-3-2054.
No. 39, etc.

The waterproof sheet of the present invention can be obtained by using the above-mentioned BPP by a known molding method such as calendar molding or extrusion sheet molding. Further, it can be used not only as a simple substance but also as a laminate by laminating it with other materials using a known multi-layer coextrusion molding machine, extrusion lamination molding machine, dry lamination molding machine or the like. Further, in the waterproof sheet of the present invention, other additives conventionally used in thermoplastic resins (for example, antioxidants, weather resistance stabilizers, antistatic agents, lubricants, antiblocking agents, antifog agents, dyes,
Pigments, oils, waxes, fillers, etc.) can be blended in appropriate amounts within the range not impairing the object of the present invention.

Examples of such additives include 2,5-di-t-butylhydroquinone and 2,2 as an antioxidant.
6-di-t-butyl-p-cresol, 4,4'-thiobis- (6-t-butylphenol), 2,2-methylene-bis (4-methyl-6-t-butylphenol), octadecyl 3- (3 ', 5'-di-t-butyl-1'-
Hydroxyphenyl) propionate, 4,4'-thiobis- (6-butylphenol), UV absorbers such as ethyl-2-cyano-3,3-diphenylacrylate, 2- (2'-hydroxy-5-methylphenyl) benzo Triazole, 2-hydroxy-4-octoxybenzophenone, dimethyl phthalate, diethyl phthalate as plasticizer, wax, liquid paraffin, phosphoric ester, pentaerythritol monostearate, sorbitan monopalmitate, sulfuric acid as antistatic agent Oleic acid, polyethylene oxide, carbon wax, ethylene bis stearamide, butyl stearate as a lubricant, carbon black as a colorant, phthalocyanine,
Quinacridone, indoline, azo pigments, titanium oxide,
Examples of fillers such as red iron oxide are glass fiber, asbestos, mica, ballastonite, calcium silicate, aluminum silicate, calcium carbonate and the like. Also, many other polymer compounds may be blended to the extent that the effects of the present invention are not impaired.

[0021]

The present invention will be described in more detail with reference to the following examples. The method and apparatus for measuring each physical property in the present invention are shown below. (1) 25 ° C Paraxylene Extractable Soluble Content (X _IS ) BPP was once dissolved in 135 ° C paraxylene, then cooled to 25 ° C to precipitate a polymer, and the soluble content was X.
_IS (% by weight) was used. (2) Analysis by 2-site model BPP was mixed in a mixed solvent of 1,2,4-trichlorobenzene / heavy benzene so that the polymer concentration became 10% by weight.
Dissolve by heating to 30 ° C. Then, ¹³ C-NMR spectrum was measured with the following apparatus and conditions, and the respective signals were obtained by Macromolecules, 13, 267 of A. Zambelli et al.
Attributable in (1980). Measuring instrument: JNM-GSX manufactured by JEOL Ltd.
400 ( ¹³ C nuclear resonance frequency 100 MHz) Pulse width: 8.0 μsec Pulse repetition time: 5.0 sec Number of integrations: 20000 times Solvent: 1,2,4-trichlorobenzene / deuterated benzene mixed solvent (75/25% by volume) Internal standard: hexamethyldisiloxane Sample concentration: 300 mg / 3.0 ml Solvent measurement temperature: 120 ° C. Next, a two-site model was analyzed to determine FP, P _P and P _f1 .

(3) Crystallization temperature and ratio of secondary peak area to main peak area (SMA) Equipment: PERKIN-ELMER DSC7 type Sample weight: Approximately 3 to 5 mg Measurement method: Temperature of sample up to 230 ° C After holding for 5 minutes, the temperature was lowered to -30 ° C at a rate of 20 ° C / minute to obtain a crystallization temperature curve. From the obtained crystallization temperature curve, the main peak temperature, the secondary peak temperature and the ratio of the secondary peak area to the main peak area (SMA) were determined. (4) Cross fractionation chromatograph device: Yuka Denshi T-150A type sample solution: Orthodichlorobenzene with a polymer concentration of 0.4% by weight TREF column: 4.6 mmΦ × 150 mm Packing agent: Glass beads Column temperature distribution: Within ± 0.1 ° C GPC column: SHODEX UT806M, 807 Detection unit: Infrared detection method (MIRAN-1A) Solvent flow rate: 1.0 ml / min Injection amount: 0.5 ml Temperature rising rate: 1 ° C / min Measurement method: Polymer The solution was introduced into TREF, and the temperature was lowered to 0 ° C. at a temperature lowering rate of 140 ° C./min.
It is kept for a minute to be adsorbed on the filler, and then the temperature is raised to 140 ° C. at the above temperature rising rate to obtain an elution curve.

(5) Tensile Elastic Modulus According to JIS K7127, the tensile rate was 5 mm / min. (6) Tensile test In accordance with JIS K7127, temperature 23 ° C, tensile speed 2
It was performed under the condition of 00 mm / min. (7) Tear strength According to JIS K7128B method, Elmendorf tear strength was measured at a temperature of 23 ° C. (8) Water vapor transmission rate According to ASTM E96, MOCON PERMA
Using a TRAN-W transmittance measuring device, the temperature was 37.8.
The measurement was performed under the conditions of ° C and 90% relative humidity. (9) Heat-sealing property Heat-sealing film is placed in a thermostatic chamber at a temperature of 23 ° C and a humidity of 50%.
After being left for 8 hours, the peel strength was 4 kg / in a 180 ° peel test.
The temperature range capable of heat fusion was determined under the condition that it has a width of 15 mm or more and that the root cutting phenomenon of the heat-sealed portion does not occur by visual observation. (10) According to MFR JIS K7210, it was measured using a melt indexer manufactured by Takara. (11) Cold resistance Cold resistance test sheet (15 cm x 15 cm, thickness 1 mm)
RHEOMETRICS, INC. Made HIG
The energy absorption amount (joule) at the time of destruction at a temperature of −20 ° C. and −40 ° C. was obtained by using HIMPACT TESTER RIT-8000.

BPP1 to BPP shown in Table 2 according to the multi-stage polymerization method described in the above-mentioned prior art as BPP.
5 was obtained. BPP5 is used for comparison.

Examples 1 to 4 and Comparative Example 1 Table 2 shows the measurement results of various physical properties of BPPs 1 to 5. Further, to 100 parts by weight of each BPP, 0.05 part by weight of di-t-butyl-p-cresol as a stabilizer and pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-) were used.
Hydroxyphenyl) propionate (0.1 parts by weight), calcium stearate (0.1 parts by weight), and ultraviolet stabilizer (HSLS944) (0.4 parts by weight) were mixed and mixed using a Kawada Seisakusho super mixer (SMV20 type),
Pelletized using a twin screw extruder (KTX37 type) manufactured by Kobe Seisakusho. The pellets thus obtained were subjected to a NVC 65 mmφ bent type composite sheet molding machine with a T-die manufactured by Nakatani Kikai Co., Ltd., a die temperature of 230 ° C., a cooling roll temperature of 40 to 60
A sheet having a thickness of 0.5 mm was prepared under the conditions of ° C and a take-up speed of 0.5 m / min. Various physical properties of each sheet were evaluated. Table 3 shows the results. In addition, the heat sealing for evaluating the heat-sealing property was performed by stacking two sheets using a heat seal tester manufactured by Tester Sangyo Co., Ltd. and pressure 2 kg / c.
m ² and pressurization time of 30 seconds, temperature 145 ° C to 5 ° C
The temperature was changed for each time and pressure bonding was performed.

Comparative Example 2 Physical properties were measured in the same manner as in the above-mentioned example except that a soft vinyl chloride sheet having a thickness of 0.5 mm was used. Table 3 shows the results.
Shown in

[0027]

[Table 2]

[0028]

[Table 3]

[0029]

INDUSTRIAL APPLICABILITY The waterproof sheet of the present invention is excellent in flexibility, tear strength and cold resistance, and is also excellent in heat-sealing property (leister processability) and light weight. It is useful in a wide range of fields such as applications.

[Brief description of drawings]

FIG. 1 is a DSC of the propylene block copolymer of the present invention.
It is an example of a crystallization temperature curve.

FIG. 2 is an example of a nuclear magnetic resonance spectrum of a propylene-ethylene copolymer.

FIG. 3 is an example showing names of respective carbons derived from a chain distribution of a propylene-ethylene copolymer.

Claims (4)

[Claims] 1. A waterproof sheet comprising a propylene-α-olefin block copolymer having the following physical properties. In a crystallization temperature curve measured using a differential scanning calorimeter, (A) main crystallization peak temperature: 85 to 95 ° C (B) main crystallization peak temperature half-value width: 3 to 10 ° C (C) secondary Crystallization peak temperature: 65 to 75 ° C. (D) Ratio of secondary crystallization peak area to main crystallization peak area: 3 to 15% 2. A propylene-α-olefin block copolymer comprising a polypropylene block in an amount of 30 to 70% by weight.
And a copolymer block of propylene and another α-olefin in an amount of 70 to 30% by weight. 3. The waterproof sheet according to claim 1, wherein the elution components measured by cross fractionation chromatography of the propylene-α-olefin block copolymer have the following proportions. (I) Elution amount below 0 ° C: 50 to 65% by weight (ii) Elution amount above 0 ° C and 90 ° C: 10 to 28% by weight (iii) Outflow amount above 90 ° C and 130 ° C: 15 to 25% by weight 4. The waterproof sheet according to claim 1, wherein the propylene-α-olefin block copolymer has the following physical properties (1) to (2). (1) Para-xylene insoluble matter at a temperature of 25 ° C .: 25 to
65% by weight (2) For the para-xylene solubles, (a) the average propylene content (F
P): 20 to 80 mol% (b) the propylene content of the high propylene content side by two-site model _(P P): ratio of 60 to 90 mol% (c) P _H occupied in the copolymer (P _f1): 0.4
0-0.90