阅读说明：本技术 一种防水卷材用高延伸率聚酯改性合金膜及其制备方法 (High-elongation polyester modified alloy film for waterproof coiled material and preparation method thereof ) 是由 张启纲 苏醒 李沅鸿 王果连 李国庆 郑明伟 王飞龙 于 2019-03-08 设计创作，主要内容包括：本发明涉及一种防水卷材用高延伸率聚酯改性合金膜及其制备方法,属于薄膜生产制造技术领域。该薄膜由上表层、芯层和下表层组成；上表层由PET和含SiO<Sub>2</Sub>抗粘结剂的PET母料组成,芯层由PET、SEBS热塑性弹性体、PE-g-MAH组成,下表层由PETG组成。制备方法是将原料按照各层的配方混合后,分别经三套挤出系统熔融、抽真空、过滤后挤出,三种熔体汇合至T型模头后挤出铸片,再经双向拉伸定型、牵引收卷、分切即可得防水卷材用合金膜。本发明聚酯改性合金膜强度高、刚性好,耐高温,尺寸稳定性好,而且具有良好的韧性和较高的延伸率,及优异的印刷性能和涂覆性能,表面无须经过任何特别的电晕处理,就可进行各种印刷或喷涂。(The inventionRelates to a high-elongation polyester modified alloy film for a waterproof coiled material and a preparation method thereof, belonging to the technical field of film production and manufacturing. The film consists of an upper surface layer, a core layer and a lower surface layer; the upper surface layer is made of PET and SiO 2 The anti-adhesive PET master batch comprises a core layer, a lower surface layer and a core layer, wherein the core layer comprises PET, SEBS thermoplastic elastomer and PE-g-MAH, and the lower surface layer comprises PETG. The preparation method comprises the steps of mixing the raw materials according to the formula of each layer, respectively melting by three sets of extrusion systems, vacuumizing, filtering, extruding, converging the three melts to a T-shaped die head, extruding a cast sheet, and performing biaxial stretching shaping, traction rolling and slitting to obtain the alloy film for the waterproof coiled material. The polyester modified alloy film has high strength, good rigidity, high temperature resistance, good dimensional stability, good toughness, higher elongation, excellent printing performance and coating performance, and can be used for various printing or spraying without any special corona treatment on the surface.)

1. The polyester modified alloy film for the waterproof coiled material is characterized in that: the film consists of an upper surface layer, a core layer and a lower surface layer; the upper surface layer is made of PET and SiO-containing₂The anti-adhesive PET master batch comprises a core layer, a lower surface layer and a core layer, wherein the core layer comprises PET, SEBS thermoplastic elastomer and PE-g-MAH, and the lower surface layer comprises PETG.

2. The polyester modified alloy film for a waterproof roll according to claim 1, characterized in that: according to the weight percentage, in the upper surface layer, the content of PET is 80% -85%, and the content of PET master batch is 15-20%; in the core layer, the content of PET is 70% -80%, the content of PE-g-MAH is 10-20%, and the content of SEBS is 5-10%.

3. The polyester modified alloy film for a waterproof roll according to claim 1, characterized in that: in the alloy film, the thickness of the upper surface layer accounts for 10-20% of the total thickness of the film, the thickness of the core layer accounts for 60-80% of the total thickness of the film, and the thickness of the lower surface layer accounts for 10-20% of the total thickness of the film.

4. The polyester modified alloy film for a waterproof roll according to claim 3, characterized in that: the total thickness of the alloy film is 25-100 mu m.

5. The method for producing the polyester modified alloy film for waterproofing membrane according to any of claims 1 to 4, comprising the steps of:

(1) uniformly mixing the components according to the composition formula of the core layer in proportion, melting and vacuumizing the mixture in a main extruder, and filtering to remove water and impurities in the raw materials to obtain a main extrusion melt serving as the core layer;

(2) uniformly mixing the components according to the composition formula of the upper surface layer and the lower surface layer in proportion, and carrying out melting and vacuumizing treatment by respective corresponding auxiliary extruders to obtain auxiliary extrusion melt serving as the upper surface layer and the lower surface layer;

(3) converging and extruding the main extrusion melt and the auxiliary extrusion melts on the upper and lower surface layers in a three-layer die head, and closely attaching the extruded mixed melt to the surface of a grounded cold drum after passing through an electrostatic adsorption wire to form a cast sheet;

(4) stripping the cast sheet from the cold drum to form a sheet, preheating the sheet, then entering a longitudinal stretching area, and completing longitudinal stretching through double-point stretching; the longitudinally stretched sheet directly enters a transverse stretching area after being preheated, transverse stretching is completed through multi-stage stretching, then the longitudinally and transversely stretched film is subjected to heat setting treatment, and finally cooling is performed;

(5) and (2) cooling the film, then feeding the cooled film into a traction device, flattening the stretched film, detecting the longitudinal and transverse thicknesses of the film by using a film thickness meter, then cutting off two waste edges, then feeding the film to a winding machine for winding, and finally slitting to obtain the alloy film for the waterproof coiled material.

6. The method for producing a polyester modified alloy film for a waterproof roll according to claim 5, characterized in that: the extrusion temperature of the main extrusion melt and the auxiliary extrusion melt is 255-275 ℃, and the water content of the main extrusion melt and the auxiliary extrusion melt is less than or equal to 50ppm after the main extrusion melt and the auxiliary extrusion melt are subjected to vacuum-pumping treatment and filter filtration.

7. The method for producing a polyester modified alloy film for a waterproof roll according to claim 5, characterized in that: the melts of the upper surface layer, the core layer and the lower surface layer respectively correspond to three sets of extrusion systems, the three melts are converged to a die head to realize three-layer co-extrusion, and the die head is an ABC three-flow-channel T-shaped die head.

8. The method for producing a polyester modified alloy film for a waterproof roll according to claim 7, characterized in that: the temperature of the die head is 270-275 ℃, and the temperature of the cold drum is 25-35 ℃.

9. The method for producing a polyester modified alloy film for a waterproof roll according to claim 5, characterized in that: the preheating temperature of longitudinal stretching is 70-80 ℃, the temperature of a slow stretching roller is 80-85 ℃, the temperature of a fast stretching roller is 35-40 ℃, and the stretching multiple is 1.5-3.5 times; the preheating temperature of the transverse stretching is 85-105 ℃, the stretching temperature is 105-110 ℃, and the stretching multiple is 1.5-3.5 times; the temperature of the heat setting treatment is 180-220 ℃.

Technical Field

The invention relates to a high-elongation polyester modified alloy film for a waterproof coiled material and a preparation method thereof, belonging to the technical field of film production and manufacturing.

Background

The waterproof coiled material is prepared by impregnating asphalt or polymer waterproof material on a matrix, covering a protective layer on one surface and a barrier film on the other surface, and finally preparing the waterproof material in the form of a coiled material. According to the difference of main composition materials, the waterproof material is divided into an asphalt waterproof coiled material, a high polymer modified asphalt waterproof coiled material and a synthetic polymer waterproof coiled material; according to different tyre bodies, the coiled materials are divided into coiled materials without tyre bodies, coiled materials with polyester tyre, coiled materials with glass fibre tyre, coiled materials with glass cloth tyre and coiled materials with polyethylene tyre. In recent years, although some novel waterproof materials appear, the overall waterproof pattern mainly comprising a high polymer modified asphalt waterproof coiled material, a high polymer waterproof coiled material and a waterproof coating is not changed, and the waterproof coiled material is still in a leading position in the application of the building waterproof material in China and accounts for about 60 percent of the waterproof material.

At present, the thin films used by waterproof coiled materials in the market mainly have two categories, one is a coiled material surface film and a matrix film with a waterproof function, and the thickness of the thin films is generally 0.04-0.2 mm; the other is a silicon coating film for coil antisticking and isolating, and the thickness of the silicon coating film is 0.025-0.05 mm. The surface film comprises a plurality of high-density polyethylene common films (HDPE), aluminum foil and PE, aluminum foil and PET, PE and aluminized PET alloy films and the like, the stretching force of the film with the width of 50mm is generally required to reach 150-200N, the elongation is more than 180%, the film is not scalded when the film is contacted with high-temperature asphalt glue at 130-180 ℃ during production of a coiled material, and in addition, the film is required to be not foamed, not layered and not faded after waterproof construction on the roof surface. The body film mainly comprises an HDPE (high-density polyethylene) crossed alloy film and a biaxially oriented polyethylene terephthalate film (PET film for short), wherein the HDPE crossed alloy film has excellent two-way tear resistance and puncture resistance, but has poor high temperature resistance (lower than 130 ℃), is easy to shrink when encountering high-temperature asphalt and seriously affects the quality of a coiled material; the commercially available PET film has high mechanical strength and good high temperature resistance, but the elongation is only about 30-120%, the requirement of deformation and cracking resistance of the waterproof coiled material cannot be met, and the produced coiled material is hard and has poor tearing property at an opening.

Disclosure of Invention

The invention aims to provide a high-elongation polyester modified alloy film for a waterproof coiled material and a preparation method thereof, which are used for preparing a self-adhesive waterproof coiled material so as to meet the development requirement of the building waterproof industry.

Aiming at the problems in the prior art, the invention develops a polyester modified alloy film with high temperature resistance, high strength and high elongation, which has the toughness of HDPE and the rigidity of PET and can meet the requirements of a novel waterproof market. The film can be used as a matrix film or a surface film of a self-adhesive waterproof coiled material when the thickness is 0.04-0.1 mm, and can be used as a release film of the waterproof coiled material when the thickness is 0.025-0.05 mm.

The purpose of the invention is realized by the following technical scheme:

a high elongation polyester modified alloy film for waterproof coiled material, which consists of an upper surface layer, a core layer and a lower surface layer; the upper surface layer consists of PET (polyethylene terephthalate) and PET master batch containing an anti-bonding agent, the core layer consists of PET, SEBS (hydrogenated styrene-butadiene block copolymer) thermoplastic elastomer and PE-g-MAH (maleic anhydride grafted polyethylene, namely polyethylene grafted with a maleic anhydride compatilizer), and the lower surface layer consists of PETG (polyethylene terephthalate-1, 4-cyclohexanedimethanol ester).

Further, in the upper surface layer, the content of PET is 80-85% and the content of PET masterbatch is 15-20% in percentage by weight.

Furthermore, in the core layer, the content of PET is 70-80 wt%, the content of PE-g-MAH is 10-20 wt%, and the content of SEBS is 5-10 wt%.

Further, the content of PETG in the lower skin layer was 100%.

Further, the PET master batch chip preferably contains Silica (SiO)₂) The anti-blocking masterbatch of (1). In the upper surface layer, silicon dioxide (SiO)₂) The addition weight of (A) is 0.1-1%.

Furthermore, the total thickness of the polyester modified alloy film is 25-100 mu m, the thickness of the upper surface layer accounts for 10-20% of the total thickness of the film, the thickness of the core layer accounts for 60-80% of the total thickness of the film, and the thickness of the lower surface layer accounts for 10-20% of the total thickness of the film.

In the method, the PET, PET master batch and PETG raw materials are respectively PET slices, PET master batch slices and PETG slices.

The performance test indexes of the alloy film for the waterproof coiled material are shown in the table 1.

TABLE 1 Performance index of polyester modified alloy film of the present invention

The invention also provides a method for preparing the alloy film for the waterproof coiled material, which comprises the steps of uniformly mixing the raw materials according to the formula, and carrying out melt plasticization, sheet casting, biaxial stretching, traction rolling and slitting on the mixture by an extruder to obtain the high-elongation polyester modified alloy film for the waterproof coiled material.

A preparation method of a high-elongation polyester modified alloy film for a waterproof coiled material comprises the following steps:

(1) uniformly mixing the components according to the composition formula of the core layer in proportion, melting and vacuumizing the mixture in a main extruder, and filtering to remove water and impurities in the raw materials to obtain a main extrusion melt serving as the core layer;

(2) uniformly mixing the components according to the composition formula of the upper surface layer and the lower surface layer in proportion, and carrying out melting and vacuumizing treatment by respective corresponding auxiliary extruders to obtain auxiliary extrusion melt serving as the upper surface layer and the lower surface layer;

(3) converging and extruding the main extrusion melt and the auxiliary extrusion melts on the upper and lower surface layers in a three-layer die head, and closely attaching the extruded mixed melt to the surface of a grounded cold drum after passing through an electrostatic adsorption wire to form a cast sheet;

(4) stripping the cast sheet from the cold drum to form a sheet, preheating the sheet, then entering a longitudinal stretching area, and completing longitudinal stretching through double-point stretching; the longitudinally stretched sheet directly enters a transverse stretching area after being preheated, transverse stretching is completed through multi-stage stretching, then the longitudinally and transversely stretched film is subjected to heat setting treatment, and finally cooling is performed;

(5) and (2) cooling the film, then feeding the cooled film into a traction device, flattening the stretched film, detecting the longitudinal and transverse thicknesses of the film by using a film thickness meter, then cutting off two waste edges, sending the film to a winding machine at a constant speed for winding, and finally slitting to obtain the alloy film for the waterproof coiled material.

In the steps (1) and (2), the extrusion temperature of the main extrusion melt and the auxiliary extrusion melt is 255-275 ℃, and after the main extrusion melt and the auxiliary extrusion melt are subjected to vacuum-pumping treatment and filter, the water content is less than or equal to 50 ppm.

In the step (3), the melts of the upper surface layer, the core layer and the lower surface layer respectively correspond to three sets of extrusion systems, three melts are converged to a die head to realize three-layer co-extrusion, and the die head is an ABC three-flow-channel T-shaped die head. The die head temperature is 270-275 ℃, and the cold drum temperature is 25-35 ℃.

In the step (4), the preheating temperature of longitudinal stretching is 70-80 ℃, the temperature of a slow stretching roller is 80-85 ℃, the temperature of a fast stretching roller is 35-40 ℃, and the stretching multiple is 1.5-3.5 times. The preheating temperature of transverse stretching is 85-105 ℃, the stretching temperature is 105-110 ℃, and the stretching multiple is 1.5-3.5 times. The temperature of the heat setting treatment is 180-220 ℃.

In the step (5), the thickness of the alloy film for the waterproof roll is 25-100 μm.

In the method, the PET used in the film core layer can be added with a certain proportion of reclaimed materials, and the reclaimed materials are waste sheets, waste films and trimming materials generated in the process of preparing the biaxially oriented PET film, so that the production cost can be greatly reduced.

The PETG chips, PET chips and master batch chips used in the above methods are commercially available products or products produced by the company (publicly available products), and the PE-g-MAH and SEBS thermoplastic elastomers are commercially available products.

Compared with the prior art, the invention has the beneficial effects that: (1) by adding the SEBS elastomer and the PE into the film core layer, the toughness and the recovery capability of the PET film are improved while the high strength and the high temperature resistance of the PET film are maintained, the elongation at break can reach more than 180%, and the requirement of deformation and cracking resistance of the waterproof coiled material is met; (2) the compatilizer is introduced by adding the PE-g-MAH, so that the dispersion of the compatilizer is facilitated, and the compatibility between PE and PET is increased; (3) the mechanical property and the thickness uniformity of the film are improved by adjusting the stretching temperature, the stretching ratio and the heat setting temperature, and the heat-resistant temperature of the film reaches over 160 ℃; (4) the lower surface layer of the film is made of PETG, has excellent printing performance and coating performance, and can be subjected to various printing or spraying without any special corona treatment on the surface.

Practice proves that the waterproof coiled material prepared by the high-elongation polyester modified alloy film has excellent tensile strength and elongation, good thermal stability and tear resistance, excellent corrosion resistance and aging resistance, and excellent waterproof effect, can be constructed on a wet base surface, has low requirement on the base layer, can avoid cracking caused by the phenomenon of low elongation of the waterproof layer due to full adhesion of the waterproof layer and the base layer when the base layer shrinks, cracks and deforms, and reaches the domestic advanced level.

Detailed Description

The polyester modified alloy film consists of an upper surface layer, a core layer and a lower surface layer, wherein the upper surface layer consists of PET slices and SiO-containing SiO₂The anti-adhesive PET master batch is prepared by PET slices, SEBS thermoplastic elastomer and PE-g-MAH (polyethylene grafted with maleic anhydride compatilizer), and the lower surface layer is prepared by PETG slices. The preparation method comprises the steps of mixing the raw materials according to the formula of each layer, respectively melting by three sets of extrusion systems, vacuumizing, filtering and extruding, converging the three melts to a T-shaped die head, extruding a cast sheet, wherein the die head is an ABC three-flow-channel T-shaped die head, and performing bidirectional stretching shaping, traction rolling and slitting on the cast sheet to obtain the alloy film for the waterproof coiled material.