JPH0655689A - Ethylene copolymer laminate - Google Patents

Abstract

PURPOSE:To examine a laminate, which solves problems and uses a material capable of being industrially manufactured easily, though the workability of polyvinyl butyral is inferior and a manufacturing process thereof is complicate because flexibility is attained by the addition of a plasticizer in polyvinyl butyral used as the intermediate film of safety glass. CONSTITUTION:An ethylene copolymer, which is composed of ethylene and at least a (meth)acrylic amide derivative and in which the content of the (meth) acrylic amide derivative is 10-60wt.%, and glass are laminated. Accordingly, performance as safety glass is satisfied under conditions that a plasticizer is not added to an intermediate film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate composed of an ethylene-based copolymer having excellent optical and mechanical properties and glass. As a laminated glass, these laminated materials exhibit extremely high performance as a windshield for automobiles or a window glass for buildings.

[0002]

2. Description of the Related Art In recent years,
As the safety level of automobiles has improved, windshield safety measures have become an indispensable and essential task for ensuring the safety of passengers. In response to such demands of the times, the fact that the use of resin-reinforced multi-layer safety glass as a windshield is being legally obligatory in every country in the world is in reality. In addition, with the increase in buildings that use glass (windows) on the exterior from the top of the design, the direction of using laminated glass as a safety glass for building window glass is also increasing from the viewpoint of ensuring safety in the event of a disaster such as an earthquake. is there.

At present, there are extremely strict standards for safety glass used for windshields of automobiles. For example, in Japan, JIS or JASO standards are set, but it is necessary to satisfy this standard while satisfying the cost requirement. Is a very difficult proposition.

To date, polyvinyl butyral (hereinafter abbreviated as PVB) has been used almost exclusively as a material for the intermediate layer of laminated glass for automobiles. This laminated glass is characterized by its excellent transparency and high penetration resistance at around room temperature, but its performance is not always satisfactory to the requirements of the times. This PV
Although B exhibits high penetration resistance near room temperature, its penetration resistance is not necessarily satisfactory in the temperature range of 0 ° C. or lower or in the temperature range of 80 ° C. or higher. Further, since flexibility is achieved by adding a large amount of plasticizer (usually about 40 wt%), there are considerable disadvantages associated with that.

In addition, PVB is produced by polymerization of polyvinyl acetate, production of PVA by saponification of polyvinyl acetate, and production of PVB by partial butyralization of PVA.
Since the manufacturing process and the multi-stage process are performed, the manufacturing process becomes complicated.

The present inventors have arrived at the present invention as a result of repeated studies on a laminate using a material which can overcome these problems in PVB and can be easily produced industrially.

[0007]

That is, the present invention is a copolymer of ethylene and at least a (meth) acrylamide derivative (hereinafter, abbreviated as an ethylene-based copolymer), which contains a (meth) acrylamide derivative. The amount is 10-6
Provided is an ethylene-based copolymer laminate, which is obtained by laminating 0% by weight of an ethylene-based copolymer and glass.

The (meth) acrylamide derivative contained in the ethylene copolymer used in the present invention means (meth) acrylamide, N-alkyl (meth) acrylamide, N,
N-dialkyl (meth) acrylamide etc. are mentioned, Specifically, N-methyl acrylamide, N-ethyl acrylamide, Nn-propyl acrylamide, N-i
so-propyl acrylamide, Nn-butyl acrylamide, N-iso-butyl acrylamide, Nt
-Butylacrylamide, N, N-dimethylacrylamide, N, N-diethylacrylamide, N-ethylmethacrylamide, Nn-propylmethacrylamide, Nt-butylmethacrylamide, N, N-dimethylmethacrylamide, N, N-diethylmethacrylamide, acryloylmorpholine and the like, preferably acrylamide, methacrylamide, N-ethylacrylamide, N-iso-propylacrylamide, Nt-butylacrylamide, N, N-dimethylacrylamide, N, N-. Diethyl acrylamide, N
Examples include -n-propyl methacrylamide and Nt-butyl methacrylamide. It is also possible to use a mixture of these.

In addition to the (meth) acrylamide derivative, the ethylene-based copolymer used in the present invention has other characteristics (for example, "adhesiveness" and "flexibility") to the ethylene-based copolymer. It is also possible to copolymerize other ethylenically unsaturated compounds for the purpose of imparting.

The term "ethylenically unsaturated compound" means a compound having an unsaturated group capable of copolymerizing with ethylene except a (meth) acrylamide derivative, such as a vinyl aromatic compound, an unsaturated nitrile compound, a vinyl ester compound,
It can be selected from (meth) acrylic acid ester compounds and the like. Specifically, the vinyl aromatic compound is
Examples thereof include styrene, α-methylstyrene, p-methylstyrene, and the like, and the unsaturated nitrile compound includes acrylonitrile, methacrylonitrile, and the like. Vinyl ester compounds include vinyl acetate, vinyl propionate, etc.,
The (meth) acrylic acid ester compound is methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, and the like. These compounds can be used in one or more kinds for the purpose of imparting adhesiveness and flexibility characteristics to the ethylene-based copolymer as described above, and the kind can be selected according to other purposes and characteristics. It is possible to

The content of the (meth) acrylamide derivative contained in the ethylene copolymer used in the present invention is 10 to 60% by weight, preferably 20 to 50% by weight. If it is less than 10% by weight, the material strength of the copolymer is insufficient, which is not preferable. On the other hand, when it exceeds 60% by weight, the flexibility of the copolymer is gradually lost and the mechanical properties of the laminated glass are deteriorated.

With respect to the content of the ethylenically unsaturated compound which can be contained in the ethylene copolymer used in the present invention, the present compound is adhesive or flexible to the ethylene copolymer. Since it is used for the purpose of imparting properties such as, a small amount is sufficient, usually 0 to 30% by weight,
Preferably, it is 0 to 20% by weight. If it exceeds 30% by weight, the optical characteristics or mechanical characteristics originally possessed by the ethylene-based copolymer are impaired, which is not preferable.

Next, the fluidity of the ethylene-based copolymer is M
FR (JIS K 7210: Condition 4) is 0.01-
It is 100 g / 10 minutes, preferably 0.1 to 50 g / 10 minutes. If it is less than 0.01 g / 10 minutes, the fluidity is low and the moldability is poor, which is not preferable. Further, when it exceeds 100 g / 10 minutes, the material strength becomes low, and the mechanical properties of the laminated glass are deteriorated, which is not preferable. These ethylene-based copolymers can be produced by a high-pressure radical copolymerization method or a solution radical copolymerization method, but those produced by a high-pressure radical copolymerization method are preferable, and 500 to 200
It is preferred to produce under a pressure of 0 kg / cm ² . The polymerization temperature is preferably 100 ° C to 300 ° C, and 1
50 ° C. to 250 ° C. is more preferable. As the initiator used in the polymerization, it is possible to select and use from among the commonly used organic peroxides, based on the polymerization temperature, the efficiency of the initiator and the like.

The ethylene copolymer thus obtained is added with various additives such as an antioxidant, an ultraviolet absorber and an anti-aging agent in order to secure its excellent properties for a long period of time. It is possible. In addition, it is possible to pre-color with a dye or the like from the viewpoint of the decorative property when the laminate with glass is used.

These ethylene-based copolymers have, as their optical and mechanical properties, properties sufficient to be laminated with glass as they are to form a laminated glass, but further increase their mechanical strength. It is also possible to carry out a cross-linking treatment for imparting heat resistance and then bond it to glass. Regarding the cross-linking treatment, a usual method such as peroxide cross-linking can be used, but it is preferable to carry out the cross-linking treatment by ionizing radiation after forming the sheet.

In such a treatment, it is possible to irradiate ionizing radiation such as an electron beam after forming the ethylene-based copolymer into a sheet by using a usual extrusion means, or at the same time when the sheet is formed. In the case of producing such a crosslinked sheet, the ethylene-based copolymer is
It is possible to process it into a sheet by a usual extrusion molding means. Here, the molding temperature is usually 60 to 150.
The temperature is 80 ° C, preferably 80 to 130 ° C. The thickness of the sheet is usually 0.2 to 1.0 mm. The irradiation dose of ionizing radiation is expressed as a function of irradiation time, and the irradiation dose required here is 5 to 30 Mrad, and about 10 Mrad is preferable. The objective criterion for determining the irradiation dose of ionizing radiation is near the irradiation dose at which the absorbed energy shows a maximum value when the absorbed energy at the time of penetration is obtained by subjecting the crosslinked sheet to a high-speed impact tester. Irradiation dose ±
3 Mrad is the preferred range. An apparatus used for crosslinking, for example, an electron beam irradiation apparatus, is almost characterized by an accelerating voltage of an electron beam, and the accelerating voltage is 50 to 1000 kV.
0 to 800 kV is preferable.

The thus obtained ethylene-based copolymer sheet or crosslinked product can be made into a laminate with glass in the same step of laminating with an autoclave as in the production of ordinary laminated glass. At that time, the conventional PV
Compared to the temperature and time used in B, the bonding can be performed at a lower temperature or a shorter time. Also,
It is possible to carry out the laminating without using an autoclave even under a hot press at 100 to 150 ° C. or equivalent conditions.

The thus obtained ethylene-copolymer / glass laminate has excellent optical properties, excellent mechanical strength such as penetration resistance, and has a small temperature dependence of mechanical strength and is wide. It can be used in the temperature range and can be applied to various laminated glass applications including automobile windshields.

The ethylene-based copolymer used in the present invention has high adhesiveness to various thermoplastic resins other than glass, and since it can be adhered at low temperature, it can be used in polycarbonate or It can also be applied as an intermediate layer of a laminate of transparent resins such as polymethylmethacrylate or an intermediate layer between glass and transparent resin. Hereinafter, more specific description will be given in the examples.

[0020]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Example 1 (1) Production of Ethylene / N, N-Dimethylacrylamide Copolymer A 2 l autoclave equipped with a stirrer was used at a temperature of 200 ° C. and a pressure of 1
Under the condition of 200 kg / cm ² , ethylene and N, N-dimethylacrylamide were simultaneously fed with t-butylperoxypivalate to produce a copolymer. In the obtained copolymer, after separating the monomers, a thin film was prepared using a hot press, and the amount of N, N-dimethylacrylamide in the copolymer was quantified by IR measurement of the film. As a result, the amount of N, N-dimethylacrylamide was 37.5% by weight. Moreover, the fluidity is 3.7 g.
/ 10 minutes (190 ° C., 2.16 kg load). (2) Production and Evaluation of Laminated Glass The ethylene / N, N-dimethylacrylamide copolymer obtained as described above was heated and pressed at 120 ° C. using a mold whose surface was coated with Teflon. ,
It was molded into a 0.76 mm thick sheet under a pressure of 20 kg / cm ² . Using the sheet thus prepared, a laminated glass (laminated glass) having this as an intermediate layer was prepared, and its physical properties were measured. That is, the above sheet is sandwiched between two pieces of glass having a thickness of 2 mm, and the pressure is 10 kg / cm ^{2 by} a heat compression press.
The laminated glass was prepared by heating at 120 ° C. for 10 minutes under the pressure of 1 to bond them together, taking them out of the press, and then cooling them by natural cooling. When the laminated glass thus produced was subjected to a penetration resistance test in accordance with JIS R 3212, it was confirmed that the laminated glass did not penetrate at all in a steel ball drop test from a height of 4 m and that it sufficiently satisfied the JIS standard. Was done. The transparency of this laminated glass is Haz.
The e value was 0.5%, and it was confirmed that the transparency was also sufficiently satisfied.

[Example 2] The ethylene / N, N-dimethylacrylamide copolymer used in Example 1 was converted into a 0.76 mm thick sheet by a heat compression press, and then an electron beam irradiation device (Nisshin Using a scanning type, EPS750 type manufactured by High Voltage Co., Ltd., a crosslinked sheet was prepared by irradiating an electron beam in the air at an accelerating voltage of 750 kV and an irradiation dose of 10 Mrad. Using the crosslinked sheet thus prepared, according to the method of Example 1,
A laminated glass (laminated glass) having this as an intermediate layer was prepared, and its physical properties were measured. The laminated glass thus prepared was subjected to a penetration resistance test in accordance with JIS R 3212. As a result, it was found that the laminated glass did not penetrate at all in a steel ball drop test from a height of 5 m and had a performance of JIS standard or higher. confirmed. The transparency of this laminated glass is Haz.
The e value was 0.5%, and it was confirmed that the transparency was also sufficiently satisfied.

Example 3 According to the method of Example 1- (1), polymerization was carried out by changing the feed amounts of ethylene and N, N-dimethylacrylamide to obtain a copolymer. After the monomer was separated from the obtained copolymer, the amount of N, N-dimethylacrylamide was quantified by IR according to the method of Example 1. As a result, the amount of N, N-dimethylacrylamide was 28.2% by weight. Liquidity is 3.
It was 5 g / 10 minutes (190 ° C., 2.16 kg load).
Using this ethylene / N, N-dimethylacrylamide copolymer, a laminated glass (laminated glass) was prepared by the method according to Example 1, and its physical properties were measured. as a result,
Laminated glass having this copolymer as an intermediate layer is JIS R
With respect to the penetration resistance test shown in 3212, it was confirmed that the steel ball did not penetrate at all in the steel ball drop test from a height of 4 m, and satisfied the JIS standard. Further, the transparency of this laminated glass was 0.8% in Haze value, and it was confirmed that the transparency was also sufficiently satisfied.

[Example 4] The ethylene / N, N-dimethylacrylamide copolymer used in Example 3 was processed into a sheet having a thickness of 0.76 mm by a heat compression press, and then the conditions shown in Example 2 were applied. -A crosslinked sheet was prepared by irradiating an electron beam under the same conditions and methods as the method. Using the crosslinked sheet thus prepared, a laminated glass (laminated glass) having this as an intermediate layer was prepared by the method according to Example 2, and its physical properties were measured. According to JIS R 3212
It was confirmed that the steel ball did not penetrate at all in the steel ball drop test from a height of 5 m with respect to the penetration resistance test shown in (3), and had performance of JIS standard or higher. Further, the transparency of this laminated glass was 0.8% in Haze value, and it was confirmed that the transparency was also sufficiently satisfied.

Example 5 According to the method of Example 1- (1), ethylene and N, N-dimethylacrylamide, and vinyl acetate as an ethylenically unsaturated compound were fed and polymerized to obtain a copolymer. It was In the obtained copolymer, after separating the monomers, the amount of N, N-dimethylacrylamide was quantified by IR according to the method of Example 1. As a result, the amount of N, N-dimethylacrylamide was 24.1% by weight, and the fluidity was 4.4 g / 10 minutes (190 ° C, 2.16 kg load). The vinyl acetate content was 3.4% by weight. This ethylene / N,
A laminated glass (laminated glass) was prepared using the N-dimethylacrylamide / vinyl acetate copolymer by the method according to Example 1, and the physical properties thereof were measured. As a result, laminated glass using this copolymer as an intermediate layer was manufactured according to JIS R 321.
With respect to the penetration resistance test shown in No. 2, it was confirmed that the steel ball did not penetrate at all in a steel ball drop test from a height of 4 m, and satisfied the JIS standard. The transparency of this laminated glass was 1.0% in Haze value, and it was confirmed that the transparency was also sufficiently satisfied.

Example 6 The ethylene / N, N-dimethylacrylamide / vinyl acetate copolymer used in Example 5 was heated and compressed into a sheet having a thickness of 0.76 mm. Conditions and methods similar to those shown
A crosslinked sheet was prepared by irradiating an electron beam by the method. Using the crosslinked sheet thus prepared, a laminated glass (laminated glass) having this as an intermediate layer was prepared by the method according to Example 2, and its physical properties were measured.
With respect to the penetration resistance test shown in 3212, it was confirmed that the steel ball did not penetrate at all in a steel ball drop test from a height of 5 m, and had performance of JIS standard or higher. The transparency of this laminated glass was 1.0% in Haze value, and it was confirmed that the transparency was also sufficiently satisfied.

Example 7 According to the method of Example 1- (1), polymerization was carried out while feeding ethylene and N-isopropylacrylamide and vinyl acetate as an ethylenically unsaturated compound to obtain a copolymer. N-isopropylacrylamide is a solid having a melting point of 60 ° C.,
It was fed in the form of being dissolved in vinyl acetate. After separating the monomers from the obtained copolymer, the amount of N-isopropylacrylamide was quantified by IR according to the method of Example 1. As a result, the amount of N-isopropylacrylamide was 15.1% by weight, and the fluidity was 1.2 g / 10 minutes (190 ° C, 2.16 kg load). The vinyl acetate content was 20.4% by weight. This ethylene / N
-Using isopropylacrylamide / vinyl acetate copolymer, a laminated glass (laminated glass) was prepared by the method according to Example 1, and its physical properties were measured. As a result, a laminated glass having this copolymer as an intermediate layer was manufactured according to JIS R 32.
With respect to the penetration resistance test shown in No. 12, it was confirmed that the steel ball did not penetrate at all in the steel ball drop test from a height of 4 m, and satisfied the JIS standard. The transparency of this laminated glass was 1.0% in Haze value, and it was confirmed that the transparency was also sufficiently satisfied.

Example 8 The ethylene / N-isopropylacrylamide / vinyl acetate copolymer used in Example 7 was heat pressed to form a sheet having a thickness of 0.76 mm, which was then shown in Example 2. Conditions similar to conditions and methods
A crosslinked sheet was prepared by irradiating an electron beam by the method. Using the crosslinked sheet thus prepared, a laminated glass (laminated glass) having this as an intermediate layer was prepared by the method according to Example 2, and its physical properties were measured.
With respect to the penetration resistance test shown in 3212, it was confirmed that the steel ball did not penetrate at all in a steel ball drop test from a height of 5 m, and had performance of JIS standard or higher. The transparency of this laminated glass was 1.0% in Haze value, and it was confirmed that the transparency was also sufficiently satisfied.

[Comparative Example] [Comparative Example 1] As a comparative example to Example, Example 1-
According to the method (1), an ethylene / N, N-dimethylacrylamide copolymer having an N, N-dimethylacrylamide content of 8.6% by weight was produced. The fluidity of this product was 7.0 g / 10 minutes (190 ° C., 2.16 kg load). Using this ethylene / N, N-dimethylacrylamide copolymer, a laminated glass (laminated glass) was prepared by the method according to Example 1, and its physical properties were measured. As a result, its transparency was poor at a Haze value of 6.2%, and it could not be used as a laminated glass.

[Comparative Example 2] According to the method of Example 1- (1), the feed amount of N, N-dimethylacrylamide was gradually increased until the N, N-dimethylacrylamide amount was 62.5% by weight. Was prepared. The fluidity of this product is 250 g / 10 minutes (190
It was confirmed that the molecular weight did not increase sufficiently, that is, it was very high (° C, 2.16 kg load). Also, as for the physical properties of the copolymer, it was a hard and brittle copolymer, and could not be evenly bonded to glass. The Haze value was as high as 10.2%, and it could not be used as a laminated glass.

[0031]

As shown in the examples, the laminate of the ethylene copolymer and the glass disclosed in the present invention has a property that is sufficiently applicable as an automobile windshield,
The development is expected.

Claims (6)

[Claims] 1. A copolymer of ethylene and at least a (meth) acrylamide derivative, wherein the ethylene-based copolymer having a (meth) acrylamide derivative content of 10 to 60% by weight is laminated with glass. And an ethylene-based copolymer laminate. 2. The ethylene-based copolymer laminate according to claim 1, wherein the (meth) acrylamide derivative is an N-alkyl-substituted acrylamide. 3. The ethylene-based copolymer laminate according to claim 1, wherein the (meth) acrylamide derivative is N, N-dimethylacrylamide. 4. The ethylene-based copolymer laminate as claimed in claim 1, wherein the ethylene-based copolymer is a product obtained by subjecting the ethylene-based copolymer to a crosslinking treatment. 5. The ethylene-based copolymer laminate according to claim 4, wherein the cross-linking in the ethylene-based copolymer laminate is caused by ionizing radiation. 6. The ethylene copolymer laminate according to claim 5, wherein the ionizing radiation in the ethylene copolymer laminate is an electron beam.