CN114474922A - Polypropylene composite sheet and preparation method thereof - Google Patents
Polypropylene composite sheet and preparation method thereof Download PDFInfo
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- CN114474922A CN114474922A CN202011158870.3A CN202011158870A CN114474922A CN 114474922 A CN114474922 A CN 114474922A CN 202011158870 A CN202011158870 A CN 202011158870A CN 114474922 A CN114474922 A CN 114474922A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
- B32B37/04—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the partial melting of at least one layer
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
- B32B37/06—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the heating method
- B32B37/065—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the heating method resulting in the laminate being partially bonded
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
- B32B37/10—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the pressing technique, e.g. using action of vacuum or fluid pressure
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2307/00—Properties of the layers or laminate
- B32B2307/50—Properties of the layers or laminate having particular mechanical properties
- B32B2307/54—Yield strength; Tensile strength
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Abstract
The invention belongs to the field of composite materials, and relates to a polypropylene composite sheet and a preparation method thereof. The polypropylene composite sheet comprises n polymer layers and n-1 polyolefin film layers arranged between two adjacent polymer layers, wherein n is an integer greater than or equal to 2; for adjacent polymer and polyolefin film layers, a portion of the polymer layer and a portion of the polyolefin film layer collectively form a melt-cured layer; each polyolefin film layer being used entirely to form the melt cured layer; the n polymer layers are the same or different, each independently consisting of a plurality of polypropylene tapes, and molecular chains in the polypropylene tapes have a high orientation. The polypropylene composite sheet material has greatly improved mechanical property, and the preparation process has the characteristic of continuity, improves the production efficiency and reduces the production cost.
Description
Technical Field
The invention belongs to the field of composite materials, and particularly relates to a polypropylene composite sheet, a preparation method of the polypropylene composite sheet, and the polypropylene composite sheet prepared by the preparation method.
Background
One of the important methods for preparing polypropylene composite sheets is a hot pressing process, which applies a certain temperature and pressure to the stacked polypropylene braids to melt and contact the surfaces of the polypropylene braids with each other. Then, cooling to solidify causes the melted portions of the polypropylene braid to recrystallize and form a matrix phase, thereby joining the polypropylene braids to one another to form a polypropylene sheet. The polypropylene composite sheet prepared by the method has the characteristics of high rigidity, high strength, good toughness, light weight and easiness in recycling and reprocessing, is easy to thermally form, can be used for manufacturing products such as luggage cases, briefcases, ice hockey shoes, sports helmets, engine bottom guard plates, radomes and the like, and has wide application and huge market potential.
GB2253420A provides a process for the preparation of a polymer composite sheet. First, the oriented polymer fibers are heated to and maintained at a hot pressing temperature, and sufficient pressure (contact pressure) is applied to the fibers to enable contact between the fibers. Then, the pressure was increased to 40 to 50MPa, the oriented fibers were held under the pressure (hot-pressing pressure) for a period of several seconds, and cooled and solidified to obtain a polymer composite sheet. The method can melt the surface part of the fiber, and the mass ratio of the molten part is between 5 and 10 percent.
WO1998015397a2 provides an improved process based on the process of GB2253420A which makes it possible to obtain polymer composite sheets with excellent properties at hot pressing pressures below 10 MPa.
Although the polypropylene composite sheet with excellent performance can be prepared by the process, the mechanical property of the polypropylene composite sheet still has improved space, and the hot pressing process is discontinuous and has low production efficiency.
Disclosure of Invention
The invention aims to overcome the defects of the existing hot pressing process and provides a polypropylene composite sheet which has excellent mechanical properties and can be continuously hot pressed and a preparation method thereof.
The first aspect of the invention provides a polypropylene composite sheet, which comprises n polymer layers and n-1 polyolefin film layers arranged between two adjacent polymer layers, wherein n is an integer greater than or equal to 2;
for adjacent polymer and polyolefin film layers, a portion of the polymer layer and a portion of the polyolefin film layer collectively form a melt-cured layer;
each polyolefin film layer being used entirely to form the melt cured layer;
the n polymer layers are the same or different, each independently consisting of a plurality of polypropylene tapes, and molecular chains in the polypropylene tapes have a high orientation.
The second aspect of the present invention provides a method for preparing a polypropylene composite sheet, comprising the steps of:
carrying out lamination hot pressing on the n polymer layers and the n-1 polyolefin film layers staggered with the n polymer layers, and cooling and solidifying to obtain the polypropylene composite sheet, wherein n is an integer greater than or equal to 2;
the hot pressing condition leads the surface of the polymer layer to be melted and the polyolefin film layer to be completely melted;
the n polymer layers are the same or different, each independently consisting of a plurality of polypropylene tapes, and molecular chains in the polypropylene tapes have a high orientation.
The third aspect of the present invention provides a polypropylene composite sheet produced by the above production method.
The invention provides a polypropylene composite sheet and a preparation method thereof, wherein the mechanical property of the polypropylene composite sheet is greatly improved, and the preparation process has the characteristic of continuity, so that the production efficiency is improved, and the production cost is reduced.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Detailed Description
The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
The invention provides a polypropylene composite sheet, which comprises n polymer layers and n-1 polyolefin film layers arranged between two adjacent polymer layers, wherein n is an integer greater than or equal to 2;
for adjacent polymer and polyolefin film layers, a portion of the polymer layer and a portion of the polyolefin film layer collectively form a melt-cured layer;
each polyolefin film layer being used entirely to form the melt cured layer;
the n polymer layers are the same or different, each independently consisting of a plurality of polypropylene tapes, and molecular chains in the polypropylene tapes have a high orientation.
According to the present invention, the polypropylene composite sheet in which polymer layers and polyolefin film layers are alternately laminated may include, for example, 2 polymer layers and 1 polyolefin film layer, or 3 polymer layers and 2 polyolefin film layers.
The polypropylene composite sheet material of the present invention is explained in detail by taking a three-layer structure as an example, and the polypropylene composite sheet material sequentially comprises a first polymer layer, a polyolefin film layer and a second polymer layer; forming a first melt cured layer from a portion of the first polymer layer and a portion of the polyolefin film layer, and forming a second melt cured layer from a portion of the second polymer layer and a portion of the polyolefin film layer; the sum of the proportions of the portions of the polyolefin film layer forming the first melt-cured layer and the portions of the polyolefin film layer forming the second melt-cured layer is the total polyolefin film layer. That is, before the melt-solidified layer is formed, the surface portions of the first polymer layer and the second polymer layer are melted, and the polyolefin film layer is completely melted.
The proportion of the molten portion can be determined as desired, and according to a preferred embodiment of the present invention, the portion of the polypropylene composite sheet forming the molten cured layer accounts for 0.25 to 50%, preferably 5 to 40%, of the total amount of the polypropylene composite sheet.
According to the present invention, the polypropylene (i.e., the material of the polymer layer) in the polypropylene composite sheet may be homo-polypropylene or random co-polypropylene. Specifically, the melt index of the homopolymerized polypropylene at 230 ℃ under the load of 2.16kg is between 2.0 and 4.0g/10min, and the isotacticity is between 95 and 98 percent; the random copolymerization polypropylene can be ethylene-propylene binary random copolymerization polypropylene and/or ethylene-propylene-1-butylene ternary random copolymerization polypropylene, and the content of propylene monomers in the copolymerization polypropylene is not less than 60 wt%.
It is further noted that the polypropylene may further contain other additives commonly used in the existing various polypropylenes, and the other additives do not adversely affect the mechanical properties of the polypropylene composite sheet provided by the present invention. Such other adjuvants include, but are not limited to: at least one of an antioxidant, a lubricant, a slipping agent, an antistatic agent, and the like. In addition, the amount of the other additives can be selected conventionally in the art, and those skilled in the art can know the amount of the other additives, and the details are not described herein. For example, the antioxidant may be at least one of antioxidant 1010, antioxidant 1076, antioxidant 164, antioxidant 168, antioxidant 264, and the like. The amount of the antioxidant can vary within wide limits.
According to the present invention, the polyolefin film as the intermediate layer may be a polyethylene film or a polypropylene film.
Further, the polyethylene film may be at least one of a cast polyethylene film, an extrusion blow molded polyethylene film, a unidirectional polyethylene stretched film, and a bidirectional polyethylene stretched film.
Further, the polypropylene film may be at least one of a cast polypropylene film, a uniaxially stretched polypropylene film and a biaxially stretched polypropylene film.
According to the invention, the polymer layer consists of a plurality of polypropylene strips, and according to a specific embodiment, the polymer layer is a polypropylene fabric obtained by weaving the polypropylene strips, and the polypropylene fabric can be a plain, twill, satin or three-dimensional polypropylene fabric; alternatively, the polymer layer may be formed from a unidirectional arrangement of polypropylene tapes. The polypropylene tapes may be woven or unidirectional either manually or mechanically.
In the present invention, the polypropylene tapes having a highly oriented molecular chain can be produced by a method conventional in the art, for example, by a method comprising the steps of: melting and extruding polypropylene granules to obtain a polypropylene sheet, carrying out unidirectional stretching on the polypropylene sheet to obtain a polypropylene sheet with high orientation degree, slitting the polypropylene sheet into polypropylene flat belts, and further slitting the polypropylene flat belts into polypropylene strips; wherein the temperature of the melt extrusion is preferably 170-260 ℃, and the temperature of the unidirectional stretching is preferably 90-160 ℃.
According to a specific embodiment of the invention, polypropylene granules are added into an extrusion calendaring or casting device, the polypropylene granules are conveyed and melted by a screw extruder and enter a multilayer composite die head to obtain a polypropylene melt, and the polypropylene melt is drawn to the surface of a casting roller to be cooled and solidified to obtain a polypropylene sheet. And (3) carrying out unidirectional stretching on the polypropylene sheet to obtain the polypropylene sheet with high orientation degree. The polypropylene sheet is cut into polypropylene flat tapes with the width of 50mm, and then the flat tapes are cut into polypropylene strips with the width of 2-3 mm.
In the present invention, the polyolefin film may be commercially available or may be prepared by a conventional method in the art.
In the present invention, the term "layer" is mainly used to represent the position relationship between different material units, the material of the polymer layer is polypropylene composed of polypropylene strips, the material of the polyolefin film layer is polyethylene film and/or polypropylene film, the polyolefin film layer is located between two polymer layers, which means that, in macroscopic view, polypropylene composed of polypropylene strips is located at two sides, and the polyolefin film is located in the middle. The term "layer" is not intended to limit the actual number of physical layers of a unit of the same material, i.e., each layer may be composed of multiple sub-layers of the same material. For example, the polyethylene film layer may comprise a plurality of polyethylene film sub-layers.
The polyolefin film layer comprising a plurality of polyolefin film sub-layers can be prepared by a conventional method in the field, taking a polypropylene film as an example, before preparation, a first polypropylene granule and a second polypropylene granule need to be added into an extrusion casting device, the extrusion casting device generally comprises a plurality of extruders, different materials can be heated in the plurality of extruders, and the materials heated by the different extruders can be extruded and cast through a same multilayer composite die head at least comprising two layers, so as to obtain a casting sheet or a casting film comprising a plurality of layers; wherein the material in each extruder is extruded from one of the layers of the multilayer composite die. Therefore, it should be easily understood by those skilled in the art that when it is desired to obtain a polypropylene film having a polypropylene surface layer attached to one side surface of a polypropylene core layer, two different extruders may be used to melt the first polypropylene pellet and the second polypropylene pellet, and the molten products are simultaneously cast by extrusion through a die comprising two layers, and the two layers obtained after extrusion are laminated together to obtain a cast polypropylene film or cast polypropylene sheet. The polypropylene casting sheet is subjected to unidirectional stretching or bidirectional stretching to obtain a unidirectional polypropylene stretched film or a bidirectional polypropylene stretched film. The preparation method of the polyethylene film is the same as the method, and raw materials are replaced by polyethylene particles.
According to the present invention, the extruder used for the extrusion casting may be a single screw extruder or a twin screw extruder. In addition, the conditions for the extrusion casting can be conventional choices, and those skilled in the art can know the conditions, and will not be described herein.
It is further noted that other additives commonly used may be included in the polyolefin film, and the other additives do not adversely affect the stretch film formability, mechanical properties, optical properties, and heat seal strength of the polyolefin film provided by the present invention. Such other adjuvants include, but are not limited to: at least one of an antioxidant, a lubricant, a slipping agent, an antistatic agent, an anti-sticking agent, and the like. In addition, the amount of the other additives can be selected conventionally in the art, and those skilled in the art can know the amount of the other additives, and the details are not described herein. The antioxidant may be at least one of antioxidant 1010, antioxidant 1076, antioxidant 164, antioxidant 168, antioxidant 264, and the like. The anti-blocking agent may be, for example, at least one of silica, calcium carbonate, glass beads, and the like. The amounts of the antioxidant and antiblocking agent can vary within wide limits.
According to the invention, the polyolefin film is incorporated mainly as an intermediate layer, and therefore the thickness of the polyolefin film is generally smaller than the thickness of the polymer layer.
According to the invention, the polymer layer is composed of a plurality of polypropylene strips, gaps exist among the polypropylene strips, and the gaps existing among the polypropylene strips in the polymer layer are filled with the surface melt of the polymer layer and the whole melt of the polyolefin film layer before the molten solidified layer is formed. To obtain better mechanical properties, the gaps existing between the polypropylene tapes should be filled as much as possible with the melt of the polymer layer surface and the entire melt of the polyolefin film layer.
According to the invention, the polypropylene composite sheet is obtained by laminating and continuously hot-pressing n polymer layers and n-1 polyolefin film layers staggered with the polymer layers.
The invention provides a preparation method of a polypropylene composite sheet, which comprises the following steps:
carrying out lamination hot pressing on the n polymer layers and the n-1 polyolefin film layers staggered with the n polymer layers, and cooling and solidifying to obtain the polypropylene composite sheet, wherein n is an integer greater than or equal to 2;
the hot pressing condition leads the surface of the polymer layer to be melted and the polyolefin film layer to be completely melted;
the n polymer layers are the same or different, each independently consisting of a plurality of polypropylene tapes, and molecular chains in the polypropylene tapes have a high orientation.
The proportion of the melted portion may be determined as desired, and according to a preferred embodiment of the present invention, the hot pressing is performed under conditions such that the melted portion of the polymer layer and the polyolefin film layer is 0.25 to 50%, preferably 5 to 40%, of the total amount of the polymer layer and the polyolefin film layer.
According to the invention, in particular, the preparation method comprises the following steps: and sending the preheated polymer layer and the polyolefin film layer into a hot-pressing unit for hot pressing, then sending the hot-pressed polymer layer and the polyolefin film layer into a cooling and curing unit, rapidly cooling under pressure, and cooling and curing to form the polymer composite sheet.
The preheating mode can be that the single-layer polymer layer and the single-layer polyolefin film layer are respectively preheated, or the n-layer polymer layer and the n-1-layer polyolefin film layer are alternately arranged to form a polymer lamination, and then the polymer lamination is subjected to overall preheating after being pre-pressed.
According to a preferred embodiment of the present invention, the preparation method comprises the steps of: the method comprises the following steps of placing n polymer layers and n-1 polyolefin film layers in a staggered mode to form a polymer lamination, then sending the polymer lamination into a preheating oven through a guide roller to be preheated, enabling the preheated polymer lamination to enter a crawler-type hot-pressing unit to be hot-pressed, enabling the hot-pressed polymer lamination to enter a cooling and solidifying unit, rapidly cooling under pressure, forming the polymer composite sheet after cooling and solidifying, and enabling the polymer composite sheet to enter a winding mechanism or be cut.
According to the present invention, the hot pressing conditions are preferably such that the gaps existing between the polypropylene tapes in the polymer layer are filled with the polymer layer surface melt and the entire melt of the polyolefin film layer, more preferably such that the gaps existing between the polypropylene tapes in the polymer layer are filled with the polymer layer surface melt and the entire melt of the polyolefin film layer.
In the method of the present invention, the preparation methods of the polypropylene tape and the polyolefin film are the same as those described above, and are not described herein again.
In the method of the present invention, the specific selection of the polypropylene and the polyolefin film, the formation manner of the polymer layer, and the relative thickness of the polymer layer and the polyolefin film layer are the same as those described above, and are not repeated herein.
According to the method of the invention, when the polyolefin film is a polyethylene film, the preheating temperature is 90-190 ℃, preferably 100-190 ℃, and more preferably 120-190 ℃; the hot pressing temperature is 155-220 ℃, preferably 155-210 ℃, and more preferably 155-200 ℃; the pressure of the hot pressing is 1-30MPa, preferably 2-20MPa, and more preferably 5-15 MPa; the temperature of the cooling solidification unit is 20-140 ℃, preferably 20-120 ℃, and more preferably 20-80 ℃.
According to the method of the invention, when the polyolefin film is a polypropylene film, the preheating temperature is 90-190 ℃, preferably 120-190 ℃, and more preferably 135-190 ℃; the temperature of the hot pressing is 170-220 ℃, preferably 170-210 ℃, and more preferably 170-200 ℃; the pressure of the hot pressing is 1-30MPa, preferably 2-20MPa, and more preferably 5-15 MPa; the temperature of the cooling solidification unit is 20-140 ℃, preferably 20-120 ℃, and more preferably 20-80 ℃.
The invention also provides the polypropylene composite sheet prepared by the preparation method.
The present invention will be further described with reference to the following examples, but the scope of the present invention is not limited to these examples.
In the following examples of the present invention,
the polypropylene is T03S produced by China petrochemical and sea-killing refining, is homopolymerized polypropylene, has a melt index (230 ℃, 2.16kg) of 3.0g/10min, and has an isotacticity of 96%.
The small multi-layer composite experimental line was purchased from the same laboratory analytical instruments, ltd, guangzhou city.
The film vertical uniaxial tension device is purchased from general laboratory analytical instruments, Inc. of Guangzhou city.
The high speed slitter was model SY-SL320, available from Siyuan digital control Equipment, Inc., Guangzhou.
The hot press adopts a multi-layer composite film forming device manufactured by Guangzhou city common laboratory analytical instruments Co.
The polypropylene film is a biaxially oriented polypropylene film, available from Qingdao Yingnuo packaging technology Co., Ltd, and has a thickness of 25 μm.
The polyethylene film was a biaxially oriented polyethylene film obtained from Xiamen packaging materials Co., Ltd and had a thickness of 25 μm.
The properties of the polypropylene composite sheet were tested according to the following methods: tensile strength, tensile modulus and strain at break, measured according to the methods specified in the standard GB/T1040.1-2018.
The proportion of the polypropylene composite sheet forming the melt-cured layer in the total amount of the polypropylene composite sheet was measured according to the method described in the literature "Controlling the Properties of Single-polymer Composites by Surface measuring of the Reinforcing Fibers" (Polymer. adv. Technol,13,1046-1054, Experimental methods).
Example 1
The polypropylene T03s was added to a small multilayer compounding line to obtain polypropylene cast sheets, where the temperature of the extrusion casting was 230 ℃ and the temperature of the casting roll was 40 ℃. And (3) carrying out unidirectional stretching on the polypropylene cast sheet to obtain a highly oriented polypropylene sheet, wherein the preheating temperature and the stretching temperature during stretching are both 145 ℃. And cutting the polypropylene flat belt by a high-speed cutting machine to obtain a polypropylene flat belt, and flat-knitting the polypropylene flat belt to obtain the polypropylene check fabric with the thickness of 243 mu m.
Respectively placing the polypropylene checked cloth and the polypropylene film into unwinding rollers, and arranging the polypropylene checked cloth and the polypropylene film from top to bottom according to the following sequence before entering a preheating unit of a hot press: (1) polypropylene checked cloth; (2) a polypropylene film; (3) polypropylene plaid; (4) a polypropylene film; (5) polypropylene scrim, resulting in a polymer laminate. And (3) preheating the polymer lamination, and then entering a hot pressing unit, wherein the hot pressing temperature is 177 ℃, the hot pressing pressure is 5MPa, and the residence time of the hot pressing unit is 6 min. And then the polymer lamination enters a cooling and solidifying unit to obtain the polypropylene composite sheet, the cold air temperature is 30 ℃, the pressure maintaining pressure is 5MPa during cooling, and the cooling time is 2 min. The preheating temperature is consistent with the hot pressing temperature.
The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
Example 2
A polypropylene composite sheet was prepared according to the method described in example 1, except that the hot pressing temperature was 182 ℃. The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
Example 3
A polypropylene composite sheet was prepared according to the method described in example 1, except that the hot pressing temperature was 187 ℃, and the resulting polypropylene composite sheet was subjected to the test, and the results are shown in table 1.
Example 4
The polypropylene T03s was added to a small multilayer compounding line to obtain polypropylene cast sheets, the temperature of extrusion casting was 230 ℃ and the temperature of casting rolls was 40 ℃. And (3) carrying out unidirectional stretching on the polypropylene cast sheet to obtain a highly oriented polypropylene sheet, wherein the preheating temperature and the stretching temperature during stretching are both 145 ℃. And cutting the polypropylene flat belt by a high-speed cutting machine to obtain a polypropylene flat belt, and flat-knitting the polypropylene flat belt to obtain the polypropylene check fabric with the thickness of 243 mu m.
Respectively placing the polypropylene checked cloth and the polyethylene film into unwinding rollers, and arranging the polypropylene checked cloth and the polyethylene film from top to bottom according to the following sequence before entering a preheating unit of a hot press: (1) polypropylene plaid; (2) a polyethylene film; (3) polypropylene plaid; (4) a polyethylene film; (5) polypropylene scrim, resulting in a polymer laminate. And (3) preheating the polymer lamination, then entering a hot pressing unit, wherein the hot pressing temperature is 177 ℃, the hot pressing pressure is 5MPa, the residence time of the hot pressing unit is 6min, then entering a cooling and curing unit to obtain the polypropylene composite sheet, the cold air temperature is 30 ℃, the pressure maintaining pressure is 5MPa during cooling, and the cooling time is 2 min. The preheating temperature is consistent with the hot pressing temperature.
The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
Example 5
A polypropylene composite sheet was prepared according to the method described in example 4, except that the hot pressing temperature was 182 ℃. The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
Example 6
A polypropylene composite sheet was prepared according to the method described in example 4, except that the hot pressing temperature was 187 ℃. The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
Comparative example 1
The polypropylene T03s was added to a small multilayer compounding line to obtain polypropylene cast sheets, the temperature of extrusion casting was 230 ℃ and the temperature of casting rolls was 40 ℃. And (3) carrying out unidirectional stretching on the polypropylene cast sheet to obtain a highly oriented polypropylene sheet, wherein the preheating temperature and the stretching temperature during stretching are both 145 ℃. And cutting by a high-speed cutting machine to obtain a polypropylene flat belt, and flat-weaving the polypropylene flat belt to obtain the polypropylene check cloth.
And (3) arranging the three layers of polypropylene lattices in a unwinding roller, preheating, then entering a hot pressing unit, keeping the hot pressing temperature at 177 ℃, the hot pressing pressure at 5MPa, keeping the hot pressing unit for 6min, then entering a cooling and curing unit to obtain the polypropylene composite sheet, keeping the cold air temperature at 30 ℃, keeping the pressure at 5MPa during cooling, and keeping the cooling time at 2 min. The preheating temperature is consistent with the hot pressing temperature. The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
Comparative example 2
A polypropylene composite sheet was prepared according to the method described in comparative example 1, except that the hot pressing temperature was 182 ℃. The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
Comparative example 3
A polypropylene composite sheet was prepared according to the method described in comparative example 1, except that the hot pressing temperature was 187 ℃. The polypropylene composite sheet obtained was subjected to the test, and the results are shown in table 1.
TABLE 1
As can be seen from examples 1-3 and comparative examples 1-3, the addition of the polypropylene film improves the tensile strength, tensile modulus and strain at break of the polypropylene composite sheet. As can be seen from examples 4 to 6 and comparative examples 1 to 3, the addition of the polyethylene film greatly improved the tensile strength of the polypropylene composite sheet, and at the same time, the strain at break was increased. However, the tensile modulus of the polypropylene composite sheet is reduced.
The above conclusion shows that, as the intermediate layer of the polypropylene composite sheet, the addition of the polypropylene film or the polyethylene film widens the hot pressing temperature window while improving the mechanical property of the polypropylene composite sheet, and can perform continuous hot pressing to improve the production efficiency.
Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
Claims (22)
1. The polypropylene composite sheet is characterized by comprising n polymer layers and n-1 polyolefin film layers arranged between two adjacent polymer layers, wherein n is an integer greater than or equal to 2;
for adjacent polymer and polyolefin film layers, a portion of the polymer layer and a portion of the polyolefin film layer collectively form a melt-cured layer;
each polyolefin film layer being used in its entirety to form the melt-cured layer;
the n polymer layers are the same or different, each independently consisting of a plurality of polypropylene tapes, and molecular chains in the polypropylene tapes have a high orientation.
2. The polypropylene composite sheet according to claim 1, wherein the portion of the polypropylene composite sheet forming the melt-cured layer is 0.25 to 50%, preferably 5 to 40% of the total amount of the polypropylene composite sheet.
3. The polypropylene composite sheet according to claim 1, wherein the polypropylene is a homo-polypropylene and/or a random co-polypropylene; the melt index of the homopolymerized polypropylene is between 2.0 and 4.0g/10min at 230 ℃ under the load of 2.16kg, and the isotacticity is between 95 and 98 percent; the random copolymerization polypropylene is ethylene-propylene binary random copolymerization polypropylene and/or ethylene-propylene-1-butylene ternary random copolymerization polypropylene, and the content of propylene monomers in the copolymerization polypropylene is not less than 60 wt%.
4. The polypropylene composite sheet according to claim 1, wherein the polyolefin film is a polyethylene film and/or a polypropylene film;
the polyethylene film is preferably at least one of a cast polyethylene film, an extrusion blow-molded polyethylene film, a unidirectional polyethylene stretched film and a bidirectional polyethylene stretched film;
the polypropylene film is preferably at least one of a cast polypropylene film, a uniaxially stretched polypropylene film and a biaxially stretched polypropylene film.
5. The polypropylene composite sheet according to claim 1, wherein the polymer layer is a polypropylene fabric obtained by weaving polypropylene tapes, preferably the polypropylene fabric is a plain, twill, satin or three-dimensional polypropylene fabric;
alternatively, the first and second electrodes may be,
the polymer layer is formed by unidirectional arrangement of polypropylene strips.
6. The polypropylene composite sheet according to claim 1, wherein the polymer layers each have a thickness greater than the thickness of the polyolefin film layer.
7. The polypropylene composite sheet according to claim 1, wherein gaps existing between the polypropylene tapes in the polymer layer are filled with the polymer layer surface melt and the entire melt of the polyolefin film layer.
8. The polypropylene composite sheet according to claim 1, wherein the polypropylene composite sheet is obtained by continuously hot-pressing n polymer layers and n-1 polyolefin film layers alternately arranged.
9. A preparation method of a polypropylene composite sheet is characterized by comprising the following steps:
carrying out lamination hot pressing on the n polymer layers and the n-1 polyolefin film layers staggered with the n polymer layers, and cooling and solidifying to obtain the polypropylene composite sheet, wherein n is an integer greater than or equal to 2;
the hot pressing condition leads the surface of the polymer layer to be melted and the polyolefin film layer to be completely melted;
the n polymer layers are the same or different, each independently consisting of a plurality of polypropylene tapes, and molecular chains in the polypropylene tapes have a high orientation.
10. The method for preparing a polypropylene composite sheet according to claim 9, wherein the hot pressing is performed under conditions such that the melted portions of the polymer layer and the polyolefin film layer are 0.25 to 50%, preferably 5 to 40% of the total amount of the polymer layer and the polyolefin film layer.
11. The method of producing a polypropylene composite sheet according to claim 9, wherein the method comprises the steps of: and sending the preheated polymer layer and the polyolefin film layer into a hot-pressing unit for hot pressing, then sending the hot-pressed polymer layer and the polyolefin film layer into a cooling and curing unit, rapidly cooling under pressure, and cooling and curing to form the polymer composite sheet.
12. The method for preparing a polypropylene composite sheet according to claim 11, wherein the preheating is performed by: preheating the single polymer layer and the single polyolefin film layer respectively, or alternately placing n polymer layers and n-1 polyolefin film layers to form a polymer lamination, and then performing overall preheating after prepressing the polymer lamination.
13. The method of producing a polypropylene composite sheet according to claim 11, wherein the method comprises the steps of: the method comprises the following steps of placing n polymer layers and n-1 polyolefin film layers in a staggered mode to form a polymer lamination, then sending the polymer lamination into a preheating oven through a guide roller to be preheated, enabling the preheated polymer lamination to enter a crawler-type hot-pressing unit to be hot-pressed, enabling the hot-pressed polymer lamination to enter a cooling and solidifying unit, rapidly cooling under pressure, forming the polymer composite sheet after cooling and solidifying, and enabling the polymer composite sheet to enter a winding mechanism or be cut.
14. The method for producing a polypropylene composite sheet according to any one of claims 9 to 13, wherein the hot pressing is performed under conditions such that gaps existing between the polypropylene tapes in the polymer layer are filled with the polymer layer surface melt and the entire melt of the polyolefin film layer.
15. The method for producing a polypropylene composite sheet according to any one of claims 9 to 13, wherein the polypropylene tapes having a high degree of orientation of molecular chains are produced by a method comprising: melting and extruding polypropylene granules to obtain a polypropylene sheet, carrying out unidirectional stretching on the polypropylene sheet to obtain a polypropylene sheet with high orientation degree, slitting the polypropylene sheet into polypropylene flat belts, and further slitting the polypropylene flat belts into polypropylene strips; wherein the temperature of the melt extrusion is preferably 170-260 ℃, and the temperature of the unidirectional stretching is preferably 90-160 ℃.
16. The method for producing a polypropylene composite sheet according to any one of claims 9 to 13, wherein the polypropylene is a homo polypropylene and/or a random copolymer polypropylene; the melt index of the homopolymerized polypropylene at 230 ℃ under the load of 2.16kg is between 2.0 and 4.0g/10min, and the isotacticity is between 95 and 98 percent; the random copolymerization polypropylene is ethylene-propylene binary random copolymerization polypropylene and/or ethylene-propylene-1-butylene ternary random copolymerization polypropylene, and the content of propylene monomers in the copolymerization polypropylene is not lower than 60%.
17. The method for preparing a polypropylene composite sheet according to any one of claims 9 to 13, wherein the polyolefin film is a polyethylene film or a polypropylene film;
the polyethylene film is preferably at least one of a cast polyethylene film, an extrusion blow-molded polyethylene film, a unidirectional polyethylene stretched film and a bidirectional polyethylene stretched film;
the polypropylene film is preferably at least one of a cast polypropylene film, a uniaxially stretched polypropylene film and a biaxially stretched polypropylene film.
18. The method for preparing a polypropylene composite sheet according to any one of claims 9 to 13, wherein the polymer layer is a polypropylene fabric obtained by weaving a polypropylene ribbon, preferably the polypropylene fabric is a plain, twill, satin or three-dimensional polypropylene fabric;
alternatively, the first and second electrodes may be,
the polymer layer is formed by unidirectional arrangement of polypropylene strips.
19. The method of any one of claims 9-13, wherein the polymer layers are each thicker than the polyolefin film layer.
20. The method for producing a polypropylene composite sheet according to any one of claims 9 to 13,
when the polyolefin film is a polyethylene film, the hot-pressing temperature is 155-220 ℃, preferably 155-210 ℃, and more preferably 155-200 ℃; when the polyolefin film is a polypropylene film, the hot-pressing temperature is 170-220 ℃, preferably 170-210 ℃, and more preferably 170-200 ℃;
the pressure of the hot pressing is 1-30MPa, preferably 2-20MPa, and more preferably 5-15 MPa;
the temperature for cooling and solidifying is 20-140 ℃, preferably 20-120 ℃, and more preferably 20-80 ℃.
21. The method for preparing a polypropylene composite sheet according to any one of claims 11 to 13, wherein when the polyolefin film is a polyethylene film, the preheating temperature is 90 to 190 ℃, preferably 100-190 ℃, more preferably 120-190 ℃; when the polyolefin film is a polypropylene film, the preheating temperature is 90-190 ℃, preferably 120-190 ℃, and more preferably 135-190 ℃.
22. A polypropylene composite sheet produced by the production method according to any one of claims 9 to 21.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003164680A (en) * | 2001-11-29 | 2003-06-10 | Hiraoka & Co Ltd | Bonded polyolefin sheet and production method thereof |
| CN1826213A (en) * | 2003-05-22 | 2006-08-30 | 英国技术集团国际有限公司 | Process for fabricating polymeric articles |
| CN107718813A (en) * | 2017-09-26 | 2018-02-23 | 江南大学 | A kind of high-performance fiber base all-polymer composite board and preparation method thereof |
| CN108025522A (en) * | 2015-09-10 | 2018-05-11 | 陶氏化学墨西哥股份公司 | Multilayer film and the product being made from it |
-
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- 2020-10-26 CN CN202011158870.3A patent/CN114474922A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003164680A (en) * | 2001-11-29 | 2003-06-10 | Hiraoka & Co Ltd | Bonded polyolefin sheet and production method thereof |
| CN1826213A (en) * | 2003-05-22 | 2006-08-30 | 英国技术集团国际有限公司 | Process for fabricating polymeric articles |
| CN101844385A (en) * | 2003-05-22 | 2010-09-29 | 英国技术集团国际有限公司 | Make the method for polymer product |
| CN108025522A (en) * | 2015-09-10 | 2018-05-11 | 陶氏化学墨西哥股份公司 | Multilayer film and the product being made from it |
| CN107718813A (en) * | 2017-09-26 | 2018-02-23 | 江南大学 | A kind of high-performance fiber base all-polymer composite board and preparation method thereof |
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