CN113211753A - Agricultural film with good aging resistance and production process thereof - Google Patents
Agricultural film with good aging resistance and production process thereof Download PDFInfo
- Publication number
- CN113211753A CN113211753A CN202110509143.5A CN202110509143A CN113211753A CN 113211753 A CN113211753 A CN 113211753A CN 202110509143 A CN202110509143 A CN 202110509143A CN 113211753 A CN113211753 A CN 113211753A
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- Prior art keywords
- film
- raw materials
- agricultural film
- aging resistance
- particles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0017—Combinations of extrusion moulding with other shaping operations combined with blow-moulding or thermoforming
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
- B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
- B29C48/10—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels flexible, e.g. blown foils
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/46—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using vanes
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
- B29K2023/04—Polymers of ethylene
- B29K2023/06—PE, i.e. polyethylene
- B29K2023/0608—PE, i.e. polyethylene characterised by its density
- B29K2023/0625—LLDPE, i.e. linear low density polyethylene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2323/04—Homopolymers or copolymers of ethene
- C08J2323/08—Copolymers of ethene
Abstract
The invention discloses an agricultural film with good aging resistance and a production process thereof, and the process specifically comprises the following steps: preparing excellent LLDPE granules, an anti-aging agent and RQT-TS for standby, weighing net content of the LLDPE granules, preparing materials by 0.8% of the anti-aging agent and 0.002% of the RQT-TS, putting the LLDPE granules, 0.8% of the anti-aging agent and 0.002% of the RQT-TS into a stirrer for stirring, preliminarily mixing the raw materials, putting the mixed raw materials into a blow molding machine for hot melting and blow molding to form a film, winding the blown film by a traction roller to roll the finished film into a cylindrical shape, and preliminarily inspecting the rolled film. According to the agricultural film with good aging resistance and the production process thereof, disclosed by the invention, firstly, the mechanical property and the anti-aging property of the agricultural film are improved, meanwhile, the light transmission effect of the agricultural film is also improved, secondly, the mixing uniformity of the film raw material and the additive can be effectively improved, the overall production efficiency of the agricultural film is not influenced, and the practicability is higher.
Description
Technical Field
The invention relates to the field of film production, in particular to an agricultural film with good aging resistance, and more particularly relates to an agricultural film with good aging resistance and a production process thereof.
Background
In the process of planting agricultural products, an agricultural film is required to be used in many cases, and the agricultural film can be generally used for covering a greenhouse for keeping temperature and providing a proper growing environment for crops, covering a ground for keeping soil humidity and moisture and the like;
firstly, the existing agricultural film usually adopts LDPE as a main material, and has poor mechanical property and aging resistance, so that the phenomena of short service life and breakage are easy to occur in the using process; secondly, in the manufacturing process of the existing agricultural film, the mixing effect between the additive and the main material is poor, and the mixing is usually carried out in a solid state, but in the feeding and hot melting processes, the uneven phenomenon exists between the raw material particles and the additive particles, which affects the quality of the film preparation.
Disclosure of Invention
The invention mainly aims to provide an agricultural film with good aging resistance and a production process thereof, which can effectively solve the problems in the background technology that: the existing agricultural film usually adopts LDPE as a main material, and has poor mechanical property and aging resistance, so that the phenomena of short service life and breakage are easy to occur in the using process; secondly, in the manufacturing process of the existing agricultural film, the mixing effect between the additive and the main material is poor, and the mixing is usually carried out in a solid state, but in the feeding and hot melting processes, the non-uniformity phenomenon exists between the raw material particles and the additive particles, and the technical problem of influencing the quality of the film preparation is solved.
In order to achieve the purpose, the invention adopts the technical scheme that:
the agricultural film with good aging resistance consists of the following raw materials in parts by weight: LLDPE particles, 0.8 percent of anti-aging agent and 0.002 percent of RQT-TS.
A production process of an agricultural film with good aging resistance specifically comprises the following steps:
the method comprises the following steps: preparing raw materials, namely preparing excellent LLDPE particles, an anti-aging agent and RQT-TS for later use;
step two: weighing the net content of LLDPE particles, and preparing materials by 0.8% of anti-aging agent and 0.002% of RQT-TS;
step three: initially mixing, namely putting LLDPE particles, 0.8 percent of anti-aging agent and 0.002 percent of RQT-TS into a stirrer for stirring, so that the raw materials are initially mixed;
step four: blow molding, namely placing the mixed raw materials into a blow molding machine for hot melting and blow molding to form a film;
step five: winding, namely winding the blown film by a traction roller to roll the finished film into a cylinder shape;
step six: performing initial inspection, namely performing initial inspection on the film rolled into a cylinder;
step seven: slitting, namely performing edge slitting and width slitting according to the size;
step eight: and final inspection, namely performing final inspection on the cut film roll.
As a further scheme of the invention, in the first step, the anti-aging agent consists of an antioxidant and a copper resisting agent, wherein the content of the antioxidant is 0.5%, and the content of the copper resisting agent is 0.3%.
As a further aspect of the present invention, in the fourth step, the specific steps of blow molding are as follows:
step 1: adding the dried polyethylene particles into a lower hopper of a blow molding machine, and entering the interior of a shell of a screw extruder from the hopper by the weight of the particles;
step 2: when the granules are contacted with the inclined edges of the spiral blades, the rotating inclined edges generate a thrust force which is vertical to the inclined edges on the raw materials, and the plastic particles are pushed forwards;
and step 3: in the pushing process, the plastic is gradually melted due to the friction between the plastic and the screw, the plastic and the machine barrel and the collision friction between particles and the external heating of the material barrel;
and 4, step 4: at the in-process that melts, some raw materialss can be through stirring vane's position, do not possess oblique faceted pebble because of stirring vane, do not possess thrust to the raw materials, and stirring vane continues to rotate under the drive of pivot for mix the raw materials again, because of receiving the raw materials and continuing to follow, the raw materials after mixing again is continuously passed.
As a further scheme of the present invention, in the sixth step, the initial inspection items include transparency inspection, particle inspection, bubble inspection and breakage inspection.
As a further aspect of the present invention, in the step eight, the final inspection items include size inspection, breakage inspection, and edge flatness inspection.
Compared with the prior art, the invention has the following beneficial effects:
by adopting LLDPE as a raw material, the LLDPE has a linear main chain, and compared with LDPE adopted by the traditional agricultural film, the LLDPE has narrower molecular weight distribution and short branched chain, so that the agricultural film produced by taking the LLDPE as the raw material has better mechanical property and aging resistance than the agricultural film taking the LDPE as the raw material, but the optical property is inferior to that of the LDPE, and 0.002 percent RQT-TS is added into the raw material to improve the optical property of the agricultural film;
through set up stirring vane in screw extruder, at the in-process that melts, some raw materialss can be through stirring vane's position, do not possess oblique prism face because of stirring vane, do not possess thrust to the raw materials, and stirring vane lasts the rotation under the drive of pivot, make and remix the raw materials, because of receiving the raw materials and continuing to follow up, the raw materials after remixing is continuously passed, can effectual improvement film raw materials and the mixing homogeneity of additive, and can not influence agricultural film's whole production efficiency yet, the practicality is higher.
Drawings
FIG. 1 is a flow chart of an agricultural film with good aging resistance and a production process thereof;
FIG. 2 is a partial sectional view of the agricultural film with good aging resistance and the screw extruder in the production process thereof.
In the figure: 1. a screw extruder housing; 2. a rotating shaft; 3. a helical blade; 4. a stirring blade.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.
As shown in fig. 1-2, an agricultural film with good aging resistance is composed of the following raw materials by weight: LLDPE particles, 0.8 percent of anti-aging agent and 0.002 percent of RQT-TS.
A production process of an agricultural film with good aging resistance specifically comprises the following steps:
the method comprises the following steps: preparing raw materials, namely preparing excellent LLDPE particles, an anti-aging agent and RQT-TS for later use;
step two: weighing the net content of LLDPE particles, and preparing materials by 0.8% of anti-aging agent and 0.002% of RQT-TS;
step three: initially mixing, namely putting LLDPE particles, 0.8 percent of anti-aging agent and 0.002 percent of RQT-TS into a stirrer for stirring, so that the raw materials are initially mixed;
step four: blow molding, namely placing the mixed raw materials into a blow molding machine for hot melting and blow molding to form a film;
step five: winding, namely winding the blown film by a traction roller to roll the finished film into a cylinder shape;
step six: performing initial inspection, namely performing initial inspection on the film rolled into a cylinder;
step seven: slitting, namely performing edge slitting and width slitting according to the size;
step eight: and final inspection, namely performing final inspection on the cut film roll.
In the first step, the anti-aging agent consists of an antioxidant and a copper resisting agent, wherein the content of the antioxidant is 0.5%, and the content of the copper resisting agent is 0.3%.
In the fourth step, the blow molding comprises the following specific steps:
step 1: adding the dried polyethylene particles into a lower hopper of a blow molding machine, and entering the interior of a shell 1 of the screw extruder from the hopper by the weight of the particles;
step 2: after the granular materials are contacted with the inclined edges of the spiral blades 3, the rotating inclined edges generate a thrust force which is vertical to the inclined edges on the raw materials, and the plastic particles are pushed forwards;
and step 3: in the pushing process, the plastic is gradually melted due to the friction between the plastic and the screw, the plastic and the machine barrel and the collision friction between particles and the external heating of the material barrel;
and 4, step 4: in the melting process, the melted raw materials pass through the position of the stirring blade 4, the stirring blade 4 does not have an inclined edge surface and does not have thrust to the raw materials, the stirring blade 4 is driven by the rotating shaft 2 to continuously rotate, so that the raw materials are remixed, and the remixed raw materials are continuously pushed due to continuous follow-up of the raw materials;
and 4, step 4: the molten plastic is filtered by a machine head to remove impurities, and then is discharged from a die head die orifice, cooled by an air ring, blown and formed by a herringbone plate.
And in the sixth step, the initial detection items comprise transparency detection, particle detection, bubble detection and breakage detection.
And step eight, the final inspection items comprise size detection, crushing detection and edge flatness detection.
According to the invention, LLDPE is adopted as a raw material, the LLDPE has a linear main chain, and compared with LDPE adopted by a traditional agricultural film, the LLDPE has a narrow molecular weight distribution and a short branch chain, so that the agricultural film produced by taking the LLDPE as the raw material has better mechanical property and aging resistance than the agricultural film taking the LDPE as the raw material, but the optical property is inferior to that of the LDPE, and 0.002% of RQT-TS is added into the raw material to improve the optical property of the agricultural film; through set up stirring vane 4 in screw extruder, at the in-process that melts, some raw materialss can pass through stirring vane 4's position, because of stirring vane 4 does not possess the inclined prism face, do not possess thrust to the raw materials, and stirring vane 4 lasts the rotation under the drive of pivot 2, make and remix the raw materials, because of receiving the raw materials and continuing to follow up, the raw materials after remixing is continuously passed, can effectual improvement film raw materials and the mixing homogeneity of additive, and can not influence agricultural film's whole production efficiency yet, the practicality is higher.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (6)
1. An agricultural film with good aging resistance is characterized in that: the agricultural film with good aging resistance is composed of the following raw materials in parts by weight: LLDPE particles, 0.8 percent of anti-aging agent and 0.002 percent of RQT-TS.
2. A production process of an agricultural film with good aging resistance is characterized by comprising the following steps: the process specifically comprises the following steps:
the method comprises the following steps: preparing raw materials, namely preparing excellent LLDPE particles, an anti-aging agent and RQT-TS for later use;
step two: weighing the net content of LLDPE particles, and preparing materials by 0.8% of anti-aging agent and 0.002% of RQT-TS;
step three: initially mixing, namely putting LLDPE particles, 0.8 percent of anti-aging agent and 0.002 percent of RQT-TS into a stirrer for stirring, so that the raw materials are initially mixed;
step four: blow molding, namely placing the mixed raw materials into a blow molding machine for hot melting and blow molding to form a film;
step five: winding, namely winding the blown film by a traction roller to roll the finished film into a cylinder shape;
step six: performing initial inspection, namely performing initial inspection on the film rolled into a cylinder;
step seven: slitting, namely performing edge slitting and width slitting according to the size;
step eight: and final inspection, namely performing final inspection on the cut film roll.
3. The production process of the agricultural film with good aging resistance, as claimed in claim 2, wherein: in the first step, the anti-aging agent consists of an antioxidant and a copper resisting agent, wherein the content of the antioxidant is 0.5%, and the content of the copper resisting agent is 0.3%.
4. The production process of the agricultural film with good aging resistance, as claimed in claim 2, wherein: in the fourth step, the blow molding comprises the following specific steps:
step 1: adding the dried polyethylene particles into a lower hopper of a blow molding machine, and entering the interior of a shell (1) of the screw extruder from the hopper by the weight of the particles;
step 2: when the granules are contacted with the inclined edges of the spiral blades (3), the rotating inclined edges generate a thrust force which is vertical to the inclined edges on the raw materials, and the plastic particles are pushed forwards;
and step 3: in the pushing process, the plastic is gradually melted due to the friction between the plastic and the screw, the plastic and the machine barrel and the collision friction between particles and the external heating of the material barrel;
and 4, step 4: in the melting process, the melted raw materials pass through the position of the stirring blade (4), the stirring blade (4) does not have an inclined edge surface and does not have thrust to the raw materials, the stirring blade (4) is driven by the rotating shaft (2) to continuously rotate, so that the raw materials are remixed, and the remixed raw materials are continuously pushed due to the continuous follow-up of the raw materials;
and 4, step 4: the molten plastic is filtered by a machine head to remove impurities, and then is discharged from a die head die orifice, cooled by an air ring, blown and formed by a herringbone plate.
5. The production process of the agricultural film with good aging resistance, as claimed in claim 2, wherein: in the sixth step, the initial detection items comprise transparency detection, particle detection, bubble detection and breakage detection.
6. The production process of the agricultural film with good aging resistance, as claimed in claim 2, wherein: in the step eight, the final inspection items comprise size detection, crushing detection and edge flatness detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110509143.5A CN113211753A (en) | 2021-05-11 | 2021-05-11 | Agricultural film with good aging resistance and production process thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110509143.5A CN113211753A (en) | 2021-05-11 | 2021-05-11 | Agricultural film with good aging resistance and production process thereof |
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| Publication Number | Publication Date |
|---|---|
| CN113211753A true CN113211753A (en) | 2021-08-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110509143.5A Withdrawn CN113211753A (en) | 2021-05-11 | 2021-05-11 | Agricultural film with good aging resistance and production process thereof |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202344813U (en) * | 2011-09-28 | 2012-07-25 | 天津市天塑科技集团有限公司四维宝诺包装分公司 | Extruder screw specially used for polyethylene film for packaging |
| CN102672953A (en) * | 2012-04-27 | 2012-09-19 | 常州商隆产业用纺织品有限公司 | Production process flow of heat-sealing plastic films |
| CN103554632A (en) * | 2013-10-21 | 2014-02-05 | 中国石油化工股份有限公司 | High-strength linear low density polyethylene film resin and preparation method thereof |
| CN105711068A (en) * | 2015-09-18 | 2016-06-29 | 安徽柒柒塑业有限公司 | Production process for PE (polyethylene) film |
| CN109401042A (en) * | 2018-11-28 | 2019-03-01 | 重庆瑞霆塑胶有限公司 | A kind of formula and processing technology of PE inflation film |
| CN109553842A (en) * | 2017-09-26 | 2019-04-02 | 中国石油天然气股份有限公司 | It is used to prepare the composition and preparation method thereof of linear low density polyethylene film |
-
2021
- 2021-05-11 CN CN202110509143.5A patent/CN113211753A/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202344813U (en) * | 2011-09-28 | 2012-07-25 | 天津市天塑科技集团有限公司四维宝诺包装分公司 | Extruder screw specially used for polyethylene film for packaging |
| CN102672953A (en) * | 2012-04-27 | 2012-09-19 | 常州商隆产业用纺织品有限公司 | Production process flow of heat-sealing plastic films |
| CN103554632A (en) * | 2013-10-21 | 2014-02-05 | 中国石油化工股份有限公司 | High-strength linear low density polyethylene film resin and preparation method thereof |
| CN105711068A (en) * | 2015-09-18 | 2016-06-29 | 安徽柒柒塑业有限公司 | Production process for PE (polyethylene) film |
| CN109553842A (en) * | 2017-09-26 | 2019-04-02 | 中国石油天然气股份有限公司 | It is used to prepare the composition and preparation method thereof of linear low density polyethylene film |
| CN109401042A (en) * | 2018-11-28 | 2019-03-01 | 重庆瑞霆塑胶有限公司 | A kind of formula and processing technology of PE inflation film |
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Application publication date: 20210806 |
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