CN109749309B - High-temperature water-soluble heat-shrinkable label film and preparation method thereof - Google Patents
High-temperature water-soluble heat-shrinkable label film and preparation method thereof Download PDFInfo
- Publication number
- CN109749309B CN109749309B CN201910081417.8A CN201910081417A CN109749309B CN 109749309 B CN109749309 B CN 109749309B CN 201910081417 A CN201910081417 A CN 201910081417A CN 109749309 B CN109749309 B CN 109749309B
- Authority
- CN
- China
- Prior art keywords
- label film
- graft copolymer
- soluble
- pva
- temperature water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Details Of Rigid Or Semi-Rigid Containers (AREA)
- Wrappers (AREA)
- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
- Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
The invention provides a high-temperature water-soluble falling type heat-shrinkable label film, which comprises the following polymers: the label film comprises at least one PVC polymer and at least one water-soluble PVA graft copolymer, wherein the alcoholysis degree of the PVA graft copolymer is more than 89%, the PVA graft copolymer is dissolved at 50-80 ℃, the weight ratio of the PVA graft copolymer is at least 20%, based on the total weight of the label film, the PVC polymer and the PVA graft copolymer with the alcoholysis degree of more than 89% are blended, and the PVA graft copolymer is dissolved at the elevated temperature, so that the label film is separated from the bottle body, and the label film is convenient to recycle.
Description
Technical Field
The invention relates to a high-temperature water-soluble falling-type heat-shrinkable label film and a preparation method thereof.
Background
The PVC heat-shrinkable label can endow bottled drinks and purified water with a 360-degree label design, a packaging effect with strong visual impact is formed by printing exquisite patterns and gorgeous colors, the perfect image and attraction of commodities on a supermarket shelf are highlighted, brand differentiation design and marketing are facilitated, and a PVC material becomes one of main label forms of the current bottled drinks due to good performance and excellent cost performance.
However, the specific gravity of the PVC heat-shrinkable label film is close to that of the PET bottle body material, and is between 1.30 and 1.40, so that the PVC heat-shrinkable label film and the PET bottle body material cannot be separated by adopting the most convenient specific gravity difference method during recovery processing, and meanwhile, because the label is printed with printing ink, the label and the PET bottle body material are different and are recovered together, the PET bottle sheet with high use value is polluted, the recycling value is reduced, and the separation efficiency is low by adopting other modes, so that great difficulty and trouble are brought to the recovery processing of the PET beverage bottle.
Disclosure of Invention
In view of the above, the present invention provides a high-temperature water-soluble heat shrinkable label film and a preparation method thereof, so as to solve the problem that the existing heat shrinkable label film is not easily separated from a PET bottle.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a high temperature water soluble heat shrinkable label film comprising the following polymers:
at least one PVC polymer, and at least one water-soluble PVA graft copolymer, wherein the PVA graft copolymer has a alcoholysis degree of more than 89% and dissolves at a temperature of 50-80 ℃, and the weight proportion of the PVA graft copolymer is at least 20% based on the total weight of the label film.
PVC polymer and PVA graft copolymer with alcoholysis degree of more than 89% are blended, and the PVA graft copolymer is dissolved at elevated temperature, so that the label film is separated from the bottle body, and is convenient to recycle.
The PVC polymer can be formed by selecting one molecular weight or polymerization degree or a combination of multiple molecular weights or polymerization degrees, the monomer for PVA graft copolymerization is preferably Methyl Methacrylate (MMA), the crystallinity and water solubility of PVA are improved by utilizing the characteristics of MMA, the processing type and the transparent type of the blend are improved, and the PVA graft copolymer has the characteristics of cold water insolubility and high-temperature water solubility.
In another preferred embodiment, the weight ratio of the PVC polymer to the PVA graft copolymer is: 50-60: 50-40, meets the requirements of the label film, and has the characteristics of PVC polymer and PVA graft copolymer.
In another preferred embodiment, the PVA graft copolymer is PVA-g-PMMA, the alcoholysis degree is more than 89%, more preferably, the alcoholysis degree is between 89% and 99%, preferably, the alcoholysis degree is 90%, 91%, 92% and 93%, optionally one or more of the mixture, and in addition, the PVA-g-PMMA graft copolymer is dissolved at the temperature of 50-80 ℃, more preferably, the PVA-g-PMMA graft copolymer is dissolved at the temperature of 60-70 ℃.
In another preferred embodiment, at least one additive is further included.
In another preferred embodiment, the additive is selected from one or more of a stabilizer, a plasticizer, a processing aid, a reinforcing agent, an internal lubricant, an external lubricant, and a colorant.
In another preferred embodiment, the stabilizer is methyl tin mercaptide 181, and in the label film, the mass parts of the PVC polymer and the PVA graft copolymer are as follows: 100 portions of stabilizer, 2.5 to 3.5 portions of plasticizer, 2 to 3 portions of dioctyl terephthalate, 2 to 3 portions of processing aid, 2 to 3 portions of ACR, 4 to 6 portions of MBS, 4 to 1.2 portions of RGH-4, 0.8 to 1.2 portions of external lubricant, 0.5 to 0.9 portions of AC-316A and 3 to 5 portions of nano titanium dioxide.
The label film prepared by the proportion formula basically preserves the characteristics of a PVC heat-shrinkable label film, has excellent various performances such as shrinkability, processability, transparency and the like, is integrated with the hydrophilic characteristic of a PVA graft copolymer, presents the characteristic of high-temperature melting, simultaneously improves the toughness of the product, has wider adaptability, is more suitable for water-based ink printing, and improves the environmental protection performance of a printed label.
The label film is white due to the nano titanium dioxide serving as the colorant, printing of white ground color can be omitted in the printing process, the process is shortened, and the cost is reduced.
The invention also provides a preparation method of the high-temperature water-soluble falling-type heat-shrinkable label film,
(1) mixing materials, namely blending the PVC polymer, the PVA graft copolymer and the additive at a certain temperature.
(2) And (3) molding, namely processing and molding the mixed material in the step (1) by a double-bubble method.
In another preferred example, in the step (1), 1a, PVC resin, a stabilizer and a plasticizer are sequentially added into a mixer;
2a, heating to 75-80 ℃, and sequentially adding a reinforcing agent, an internal lubricant and a PVA graft copolymer;
3a, continuously heating to 95-100 ℃, and adding an external lubricant and a coloring agent;
and 4a, heating to 125 ℃, putting the mixed materials in the mixer into a cooling mixer for cooling, and discharging when the temperature is lower than 45 ℃.
According to the characteristics of the materials in the formula, the main materials or the additives are added in batches according to different temperatures, so that the uniform distribution of the mixed materials and uniform performance are facilitated, and the quality of the label is improved.
In another preferred example, the specific process flow in the step (2) is as follows, blend → extruder plastification → film blowing head → a bubble inflation molding → air bath heating → secondary inflation → cooling and shaping → drawing → curling → splitting → packaging → finished product.
In another preferred example, in the step (2), one bubble is blown upwards, two bubbles are blown downwards, the air bath is heated to 80-87 ℃, and the secondary blowing ratio is 2.1-2.5: 1.
The secondary bubble forming controls the blowing and stretching proportion of the film in the longitudinal direction and the transverse direction, and combines the characteristics of the PVC polymer and the PVA graft copolymer and the overall formula of the film, so that the produced film has high shrinkage, high stability and excellent performance.
In another preferred example, in the step (2), the extruder temperature: 135 ℃ 140 ℃, 170 ℃ 180 ℃, 185 ℃ 195 ℃, 200 ℃ 210 ℃ 220 ℃, and the temperature of the connecting section: the temperature of the mould is 200 ℃ to 210 ℃, the mixing effect is good, the material distribution is uniform, and the physical properties of the material are well preserved.
The invention provides a high-temperature melting-falling type thermal contraction label film, which effectively improves the efficiency of separating a label from a bottle body, promotes the recycling, develops a corresponding preparation method aiming at the label film, effectively preserves the performance of each material and further improves the performance of the label film.
Detailed Description
The following detailed description of the embodiments of the present invention is provided in connection with the examples to make the technical solutions of the present invention easier to understand and master.
The invention provides a high-temperature water-soluble heat-shrinkable label film, which is prepared by blending a PVC polymer and a PVA graft copolymer, wherein on one hand, the good performance and excellent cost performance of a PVC material are utilized, on the other hand, the water-soluble characteristic of the PVA is utilized, the low-temperature insolubility and high-temperature solubilization characteristics of the PVA are realized by means of graft copolymerization, MMA is introduced as a copolymerization graft monomer aiming at the relation between the water solubility and the alcoholysis degree of the PVA, the chemical structure and the regularity of a polyvinyl alcohol molecular chain are changed, the intermolecular and intramolecular hydroxyl effects are reduced, the water solubility of the polyvinyl alcohol is improved, meanwhile, the compatibility between the PVA and the PVC is increased by utilizing a PMMA molecular chain segment in the copolymer, and the processability and the transparency of a blend are improved, so that the polyvinyl alcohol-soluble label film is.
The high-temperature water-soluble heat-shrinkable label film comprises the following mixed material formula components:
TABLE 1
| The components in the formula | Function of | Dry blend of heat-shrinkable label film (parts by mass) |
| PVC resin + PVA-g-PMMA | Principal raw materials | 100 |
| Methyl tin mercaptide 181 | Stabilizer | 2.5-3.5 |
| Terephthalic acid dioctyl ester | Plasticizer | 2-3 |
| ACR | Processing aid | 2-3 |
| MBS | Reinforcing agent | 4-6 |
| RGH-4 | Internal lubricant | 0.8-1.2 |
| AC-316A | External lubricant | 0.5-0.9 |
| Nano titanium white powder | Coloring and opening | 3-5 |
Example 1: the PVC polymer adopts resin with average polymerization degree of 1000, the molecular weight is 6-7 ten thousand, and the mass ratio of the PVC polymer to the PVA-g-PMMA graft copolymer is as follows: 60/40, respectively;
example 2: the mass ratio of the PVC polymer to the PVA-g-PMMA graft copolymer is as follows: 50/50, the rest being identical to those of example 1.
Comparative example: the PVC polymer is only used as a main raw material, the mass portion is 100 portions, and the rest is consistent with the embodiment 1 and 2.
Preparation of Label film
1. Preparing a PVA-PMMA graft copolymer;
PVA selects products with alcoholysis degree of more than or equal to 99% and polymerization degree of 1700-2300, such as 1788 and 1799;
adding PVA into deionized water, heating to prepare an aqueous solution with the concentration of 1.0g/L, metering the aqueous solution of PVA, adding into a reactor, opening a stirrer, replacing air in the reactor with nitrogen, adding a potassium persulfate (KSP) initiator with the mol ratio of 0.08-0.1% of the PVA under the protection of nitrogen, heating to 65 ℃, dropwise adding methyl methacrylate with the addition of 0.9-1.1 times of the mol number of the PVA under the stirring condition, reacting for 5 hours under the stirring condition at 65 ℃ after dropwise adding is finished, and stopping the reaction, wherein the grafting ratio of the PVA reaches more than 90%. Stirring and cooling to room temperature, demulsifying with 0.5% aluminum sulfate solution, filtering, washing to neutrality, drying in an oven at 50-60 ℃, cooling to room temperature to obtain a powdery PVA-g-PMMA graft copolymer product, wherein the grafting rate is more than 90% by calculation, and the grafting rate in the embodiment is 92%.
2. Preparing a thermal shrinkage label film dry mixture and adding and mixing a PVA-g-PMMA graft copolymer;
the components in the formula are mixed into a uniform dry mixture in a form of matching a high-speed mixer and a cooling (low-speed) mixer.
Sequence of addition during mixing
1a, adding PVC resin, a stabilizer and a plasticizer in the rotating process of a high-speed mixer;
2a, when the temperature of the high-speed mixer is increased to 75-80 ℃, MBS, ACR, RGH-4 and PVA-PMMA graft copolymer are added;
3a, when the temperature of the high-speed mixer is increased to 95-100 ℃, adding AC-316A and nano titanium dioxide;
4a, when the temperature of the high-speed mixer rises to about 125 ℃, putting the mixture into a cooling mixer, stirring and cooling, and discharging when the temperature of the cooling mixer is below 45 ℃ for later use.
3. The PVC/PVA-PMMA blended heat-shrinkable label film is formed by blowing;
the method adopts a double-bubble method thermal shrinkage film forming mode of one-bubble up-blowing and two-bubble down-blowing which is formed by heating in a two-bubble air bath and cooling and shaping in low-temperature cold air.
The process flow comprises the following steps:
blend → extruder plastification → film blowing head → one-bubble inflation molding → air bath heating → secondary inflation → cooling shaping → traction → curling → cutting → packaging → finished product.
Extrusion and film blowing:
equipment: the single-screw extruder has a screw diameter of 65mm, a screw length-diameter ratio of 29:1 and a screw compression ratio of 2.8: 1.
2-3 layers of stainless steel filter screens with the aperture of 0.10-0.15mm are additionally arranged in front of the neck mould; the diameter of the mouth mold of the film blowing mold is 90-150mm, the gap of the mouth mold is 0.8-1.1mm, and the double-air-port air ring is arranged.
Extruder temperature: 135 ℃ 140 ℃, 170 ℃ 180 ℃, 185 ℃ 195 ℃, 200 ℃ 210 ℃ 220 ℃. Temperature of the connection section: 210 ℃ and 220 ℃. The mold temperature is 200-210 ℃. The heating temperature of the air bath is 80-87 ℃, and the secondary blow-up ratio is 2.1-2.5:1
4. Comparison of film Properties
Comparison of test Properties of Heat-shrinkable Label films
Note: 【1】 And (3) testing the dissolution rate of the high-temperature water label: soaking the PET bottle with the shrinkage label in 68 ℃ high-temperature water for 30S, observing the change condition of the label, and automatically dropping the label when the PET bottle is taken away from the water bath, wherein 10 labels are used in each group, and the average value of 3 groups is a test value.
The label which does not automatically fall off is in a mesh shape with a large number of holes because PVA is dissolved by high-temperature water, and can be easily separated from PET by hands.
As can be seen from the table, compared with the heat-shrinkable label film mainly made of PVC polymer, the heat-shrinkable label film prepared by the present invention has substantially the same shrinkage rate, slightly reduced tensile strength, but improved elongation at break, i.e., improved toughness, but the present invention has an important characteristic, i.e., high temperature water-soluble characteristic, thereby realizing automatic separation of the label film from the bottle body and improving recycling convenience.
The above is, of course, only a specific application example of the present invention, and the scope of the present invention is not limited in any way. All the technical solutions formed by equivalent transformation or equivalent replacement fall within the protection scope of the present invention.
Claims (9)
1. The high-temperature water-soluble heat-shrinkable label film is characterized by comprising the following polymers:
at least one PVC polymer, and at least one water-soluble PVA graft copolymer, the PVA graft copolymer is PVA-g-PMMA, wherein the PVA graft copolymer has alcoholysis degree of more than 89% and is dissolved at 50-80 ℃, and the weight proportion of the PVA graft copolymer is at least 20% based on the total weight of the label film.
2. The high-temperature water-soluble heat shrinkable label film of claim 1, wherein the weight ratio of the PVC polymer to the PVA graft copolymer is as follows: 50-60: 50-40.
3. A high temperature water soluble heat shrinkable label film of claim 1, further comprising at least one additive.
4. A high temperature water-soluble heat shrinkable label film of claim 3, wherein said additives are selected from one or more of the group consisting of stabilizers, plasticizers, processing aids, reinforcing agents, internal lubricants, external lubricants and colorants.
5. The method for producing a high-temperature water-soluble falling-type heat shrinkable label film according to claim 1,
(1) mixing materials, namely blending PVC polymer, PVA graft copolymer and additive at a certain temperature;
(2) and (3) molding, namely processing and molding the mixed material in the step (1) by a double-bubble method.
6. The method for preparing a high-temperature water-soluble falling type heat shrinkable label film according to claim 5,
in the step (1), 1a, sequentially adding PVC resin, a stabilizer and a plasticizer into a mixer;
2a, heating to 75-80 ℃, and sequentially adding a reinforcing agent, an internal lubricant and a PVA graft copolymer;
3a, continuously heating to 95-100 ℃, and adding an external lubricant and a coloring agent;
and 4a, heating to 125 ℃, putting the mixed materials in the mixer into a cooling mixer for cooling, and discharging when the temperature is lower than 45 ℃.
7. The method for preparing a high-temperature water-soluble falling type heat shrinkable label film according to claim 5, wherein the specific process flow in the step (2) is as follows, blend → extruder plastification → film blowing head → one-bubble inflation molding → air bath heating → secondary inflation → cooling shaping → traction → curling → slitting → packaging → finished product.
8. The method for preparing a high-temperature water-soluble falling type heat shrinkable label film according to claim 7, wherein in the step (2), the first bubble is blown upwards, the second bubble is blown downwards, the air bath is heated to 80-87 ℃, and the secondary blowing ratio is 2.1-2.5: 1.
9. The method for preparing a high-temperature water-soluble falling type heat shrinkable label film according to claim 7, wherein in the step (2), the extruder temperature: 135 ℃ 140 ℃, 170 ℃ 180 ℃, 185 ℃ 195 ℃, 200 ℃ 210 ℃ 220 ℃, and the temperature of the connecting section: 210 ℃ and 220 ℃, and the mold temperature is 200 ℃ and 210 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910081417.8A CN109749309B (en) | 2019-01-28 | 2019-01-28 | High-temperature water-soluble heat-shrinkable label film and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910081417.8A CN109749309B (en) | 2019-01-28 | 2019-01-28 | High-temperature water-soluble heat-shrinkable label film and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109749309A CN109749309A (en) | 2019-05-14 |
| CN109749309B true CN109749309B (en) | 2021-05-18 |
Family
ID=66406410
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910081417.8A Active CN109749309B (en) | 2019-01-28 | 2019-01-28 | High-temperature water-soluble heat-shrinkable label film and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109749309B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107353548A (en) * | 2017-08-15 | 2017-11-17 | 安徽华猫软包装有限公司 | One kind hydrolysis plastic sheeting and preparation method thereof |
| CN108164871A (en) * | 2017-12-26 | 2018-06-15 | 宜兴市光辉包装材料有限公司 | The no super PVC thermal contractive labels membrane preparation method of plasticiser |
| CN109181183A (en) * | 2018-08-24 | 2019-01-11 | 中山市新领航塑化科技有限公司 | A kind of preparation method of water resistance PVA Biodegradable films |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9103129B2 (en) * | 2010-10-12 | 2015-08-11 | Tarkett Gdl | Process for the production of a surface covering having a barrier layer |
-
2019
- 2019-01-28 CN CN201910081417.8A patent/CN109749309B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107353548A (en) * | 2017-08-15 | 2017-11-17 | 安徽华猫软包装有限公司 | One kind hydrolysis plastic sheeting and preparation method thereof |
| CN108164871A (en) * | 2017-12-26 | 2018-06-15 | 宜兴市光辉包装材料有限公司 | The no super PVC thermal contractive labels membrane preparation method of plasticiser |
| CN109181183A (en) * | 2018-08-24 | 2019-01-11 | 中山市新领航塑化科技有限公司 | A kind of preparation method of water resistance PVA Biodegradable films |
Non-Patent Citations (1)
| Title |
|---|
| 热收缩标签;杨涛;《塑料包装》;20071231;第17卷(第5期);第45-49页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109749309A (en) | 2019-05-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3237913B2 (en) | Melt strength improver for aromatic polyester | |
| CN101838445B (en) | PETG blow molding film and preparation method thereof | |
| CA1062840A (en) | Blends of copolyesters and ethylene/carboxylic acid copolymers which are at least ten percent neutralized | |
| CN101831170B (en) | High viscosity PA6/PE alloy and preparation method thereof | |
| CN109720066B (en) | Polyvinyl alcohol/polypropylene composite film and preparation method thereof | |
| CN113861636B (en) | High-stiffness high-toughness fully-degradable PBAT/PLA resin composition and preparation method thereof | |
| CN109071717A (en) | The thermoplasticity formulation of melt strength with raising | |
| CN102993709A (en) | Polyamide 6 (PA6) plastic alloy, preparation method and application thereof | |
| CN109720055A (en) | Polyving alcohol/polylactic acid laminated film and preparation method thereof | |
| CN106494046B (en) | A kind of biology base heat shrink films that can be degradable | |
| CN106349411A (en) | Toughening modifying agent for transparent polyvinyl chloride product and high-transparency polyvinyl chloride mixture | |
| CN109721904A (en) | Polyvinyl alcohol film and combinations thereof and preparation method | |
| CN107459735B (en) | Environment-protective polychloroethylene material composition and its preparation method and application | |
| CN114231005B (en) | PC/ABS alloy material suitable for INS diaphragm base material and preparation method thereof | |
| CN109749309B (en) | High-temperature water-soluble heat-shrinkable label film and preparation method thereof | |
| CN109721905A (en) | Polyvinyl alcohol film and combinations thereof and preparation method | |
| CN109720060A (en) | Polyvinyl alcohol polyethylene laminated film and preparation method thereof | |
| CN109401160A (en) | Wide-angle curved transparent is without scratch AS alloy laser engraving material and preparation method thereof | |
| CN117106289A (en) | Thermoplastic composite laminated material and preparation method thereof | |
| CN106939112A (en) | A kind of high glaze HIPS/ recycled PET bottles piece composite and preparation method thereof | |
| CN114836010A (en) | Biodegradable packaging film material | |
| JP2000336256A (en) | Resin composition for calendering | |
| CN113843999A (en) | Preparation method of polybutylene adipate/terephthalate film | |
| WO2007040041A1 (en) | Thickeners for thermoplastic polyester resins, thermoplastic polyester resin compositions containing the same, and moldings of the compositions | |
| CN115490978B (en) | Impact-resistant transparent PMMA material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |