CN103290741B - A kind of preparation comprising the packaging material of string and foamed plastic waste - Google Patents

Abstract

The invention relates to a packaging material containing plant fiber and foamed plastic waste and its preparation, belonging to the technical field of packaging materials. Including 50-100 parts by mass of plant fiber, 50-100 parts by mass of waste expanded polystyrene plastic particles, 10-25 parts by mass of adhesive and 10-25 parts by mass of water-resistant agent; expanded polystyrene The particle size of the plastic particles is between 0.3 and 1.0 mm; the binder is at least one of carboxymethyl cellulose and polyvinyl alcohol, and the mass ratio of carboxymethyl cellulose and polyvinyl alcohol is (0-50 ): (100-50), the water-repellent agent is urea-formaldehyde resin or melamine-formaldehyde resin. Using the wet forming principle and method of pulp molding, plant fibers and waste expanded polystyrene particles crushed to a certain size and additives are dispersed in water, and then dehydrated on both sides, dried, hot-pressed and shaped, and die-cut. The cushioning packaging material of the present invention has relatively high water resistance.

Description

Preparation of a packaging material containing plant fiber and foamed plastic waste

technical field

The invention relates to a cushioning packaging material, in particular to a pulp molded product containing plant fibers and foamed plastic wastes with cushioning performance and a preparation method thereof, belonging to the technical field of packaging materials.

Background technique

Pulp molding uses plant fiber as the main raw material, adds some auxiliary materials, and adopts a special molding method for molding. After drying, hot-pressing shaping, and die-cutting, the designed special-shaped products are obtained. In recent years, my country's pulp molded products have developed rapidly. my country's pulp molded products were mainly used in egg trays at first, and then gradually expanded to industrial instruments, electronic components, household appliances and kitchen utensils. Pulp molding has the advantages of good shock resistance, certain cushioning properties, large specific gravity, non-toxic combustion, and 100% recyclable and reusable.

Polystyrene expanded plastic (EPS) is made of polystyrene resin as the main body, adding foaming agent and other additives. It is currently the most widely used cushioning material. Polystyrene foam is widely used in the cushioning packaging of various precision instruments, meters, household appliances, etc., and can also be directly made into packaging containers such as cups, plates, and boxes to package items. Styrofoam products are bulky, used in a large amount, and difficult to decompose, so their recycling has attracted much attention.

Compared with pulp molded products, expanded polystyrene has the advantages of good shock resistance, good cushioning performance and small specific gravity. However, compared with pulp molded products, the resource recovery and recycling of expanded polystyrene are relatively poor. Combustion has the disadvantage of toxicity, and it will not decompose naturally, which is the source of white pollution.

The present invention gives full play to the advantages of plant fibers, utilizes expanded polystyrene waste, and adopts the principle and method of pulp molding to produce a water-resistant cushioning packaging material containing plant fibers and foam plastic waste, so as to achieve resource utilization and The dual role of environmental protection. This kind of cushioning packaging material can be widely used in the field of protective packaging to protect products from damage during transportation.

Contents of the invention

The purpose of the present invention is to adopt the wet forming principle and method of pulp molding to disperse plant fibers and waste expanded polystyrene particles and additives crushed to a certain size in water, and then perform double-sided dehydration, shaping, drying and drying. Heat-press setting to prepare cushioning packaging materials containing plant fibers and foam plastic waste.

Another object of the present invention is that the prepared cushioning packaging material comprising plant fiber and foamed plastic waste can replace expanded polystyrene and be used as a cushioning material in the protective packaging of goods.

The cushioning packaging material of the present invention has relatively high water resistance, and can also be used to make waterproof cushioning packaging materials and products, which overcomes the disadvantage that conventional pulp molded products do not have water resistance.

The present invention adopts the pulp molding technology and applies it to the composite packaging material containing plant fiber and foamed plastic waste, so that the composite packaging material not only has cushioning packaging performance, but also has water resistance performance, and at the same time has It is conducive to the recycling and recycling of plastic waste, and is conducive to environmental protection and resource conservation.

The invention adopts the wet molding method of pulp molding to prepare plastics containing plant fibers and waste expanded polystyrene, and the prepared cushioning packaging materials or products have water resistance, novelty and innovation.

The water-resistant cushioning packaging material containing plant fiber and foam plastic waste of the present invention is characterized in that it includes 50-100 parts by mass of plant fiber, 50-100 parts by mass of waste expanded polystyrene plastic particles, and 10-100 parts by mass of waste expanded polystyrene plastic particles. 25 parts by mass of binder and 10-25 parts by mass of water-resistant agent; the particle size of expanded polystyrene plastic particles is between 0.3-1.0 mm; the binder is made of carboxymethyl cellulose and polyvinyl alcohol At least one, preferably carboxymethyl cellulose in the binder mass percentage is not higher than 50%, more preferably 30% to 50%. The water-resistant agent is urea-formaldehyde resin or melamine-formaldehyde resin.

The preparation method of the above-mentioned water-resistant cushioning packaging material containing plant fibers and foamed plastic wastes is a pulp molding method using double-sided dehydration, including the following steps:

(1) A mixture of plant fibers and waste expanded polystyrene plastic particles

Under the action of stirring, disperse the solid plant fiber in water, the mass percentage concentration of the plant fiber is 10% to 20%, then add waste expanded polystyrene particles, add adhesive and water resistant agent in turn, stir and mix evenly;

(2), dehydration and molding

Pour the above mixture into a mold with a filter, close the mold, and squeeze the filter. The mixture sandwiched between the two filters is dehydrated on both sides under pressure, and the water in the mixture is removed through the filter. to obtain a mixed material containing plant fibers and waste foamed plastic particles, a binder and a water-resistant agent, and the mixed material is wet and solid. Generally, it contains 45wt% to 70wt% moisture (referring to the moisture content of pulp fibers, excluding foam plastics).

(3), drying and hot pressing setting

The mixed material obtained in step (2) is placed in a mold, dried in an oven at a drying temperature of 100°C, and hot-pressed in a hot press at a temperature of 125°C to 150°C to obtain Mold-shaped cushioning packaging material.

Because the obtained material contains expanded polystyrene particles, the material has relatively good cushioning performance, which is better than that of conventional pulp molded products.

At the same time, during the drying process of the material in the mold, due to the chemical crosslinking reaction between the melamine formaldehyde resin and between the melamine formaldehyde resin and the plant fiber and polyvinyl alcohol, the hydrophilicity such as the cellulose hydroxyl group in the plant fiber The group is reduced or even does not exist due to the cross-linking chemical reaction with the water-resistant agent urea-formaldehyde resin or melamine-formaldehyde resin, so that the obtained buffer material has water-resistant performance.

Detailed ways

The present invention will be described in further detail below in conjunction with the examples, but the protection scope of the present invention is not limited to the range indicated by the examples.

Example 1

Raw material: bleached softwood pulp, beating degree 28°SR. The waste expanded polystyrene foam particles have a density of 0.03g/cm ³ , and the particle size after crushing is 0.3 mm to 0.5 mm. The binder is carboxymethyl cellulose and polyvinyl alcohol. The water repellant is melamine formaldehyde resin.

Preparation steps and product performance:

First, 100 parts of bleached softwood pulp are evenly dispersed in 1000 parts of water under stirring, which is equivalent to a pulp concentration of 10%. Then add 100 parts of expanded polystyrene plastic particles, 5 parts of carboxymethyl cellulose, 10 parts of polyvinyl alcohol, and 10 parts of melamine formaldehyde resin, and disperse evenly to obtain a mixture containing bleached softwood pulp and expanded polystyrene plastic particles. , carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin and water suspension mixture.

Pour the above mixture into a mold with a filter screen, close the mold, and squeeze the filter screen, and the mixture sandwiched between the two filter screens is dehydrated on both sides under pressure to obtain bleached softwood pulp, foamed polystyrene Wet solid mixture of styrene plastic granules, carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin.

Put the above-mentioned wet solid mixture into another mold, dry in an oven at a drying temperature of 100°C, and perform hot pressing in a hot press at a temperature of 125°C to 150°C to obtain bleached needles. Cushioning packaging materials for leaf wood pulp and expanded polystyrene foam waste. The product has a density of 0.53g/cm ³ and good cushioning performance; the surface water absorption quality of the product is 5g/m ² and has good water resistance.

Example 2

Raw material: bleached bamboo pulp, beating degree 32°SR. The waste expanded polystyrene foam particles have a density of 0.03g/cm ³ , and the particle size after crushing is 0.3 mm to 0.5 mm. The binder is carboxymethyl cellulose and polyvinyl alcohol. The water repellant is melamine formaldehyde resin.

Preparation steps and product performance:

First, 100 parts of bleached bamboo pulp are evenly dispersed in 1000 parts of water under stirring, which is equivalent to a pulp concentration of 10%. Then add 100 parts of expanded polystyrene plastic particles, 5 parts of carboxymethyl cellulose, 10 parts of polyvinyl alcohol, 15 parts of melamine formaldehyde resins successively, disperse evenly, obtain comprising bleached bamboo pulp, expanded polystyrene plastic particles, Suspension mixture of carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin and water.

Pour the above mixture into a mold with a filter screen, close the mold, and squeeze the filter screen, and the mixture sandwiched between the two filter screens is dehydrated on both sides under pressure to obtain bleached bamboo pulp and expanded polystyrene plastic. Wet solid mixture of granules, carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin.

Put the above-mentioned wet solid mixture into another mold, dry in an oven at a drying temperature of 100°C, and perform hot pressing in a hot press at a temperature of 125°C to 150°C to obtain bleached bamboo Cushioning packaging materials for pulp and expanded polystyrene foam waste. The product has a density of 0.61g/cm ³ and good cushioning performance; the surface water absorption quality of the product is 5g/m ² and has good water resistance.

Example 3

Raw material: bleached coniferous wood, beating degree 28°SR. Bleached hardwood pulp, beating degree 30°SR. The waste expanded polystyrene foam particles have a density of 0.03g/cm ³ , and the particle size after crushing is 0.3 mm to 0.5 mm. The binder is carboxymethyl cellulose and polyvinyl alcohol. The water repellant is melamine formaldehyde resin.

Preparation steps and product performance:

First, 30 parts of bleached softwood pulp and 70 parts of hardwood pulp are evenly dispersed in 1000 parts of water under stirring, which is equivalent to a pulp concentration of 10%. Then add 100 parts of expanded polystyrene plastic particles, 5 parts of carboxymethyl cellulose, 10 parts of polyvinyl alcohol, 15 parts of melamine formaldehyde resin, and disperse evenly to obtain bleached hardwood pulp, bleached softwood pulp, foamed Suspended mixture of polystyrene plastic particles, carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin and water.

Pour the above mixture into a mold with a filter screen, close the mold, and squeeze the filter screen, and the mixture sandwiched between the two filter screens is dehydrated on both sides under pressure to obtain bleached hardwood pulp, bleached softwood pulp, A wet solid mixture of expanded polystyrene plastic granules, carboxymethyl cellulose, polyvinyl alcohol, and melamine formaldehyde resin.

Put the above-mentioned wet solid mixture into another mold, dry in an oven at a drying temperature of 100°C, and perform hot pressing in a hot press at a temperature of 125°C to 150°C to obtain a bleached broadsheet Cushioning packaging materials for leaf wood pulp, bleached softwood pulp and expanded polystyrene foam waste. The product has a density of 0.57g/cm ³ and good cushioning performance; the surface water absorption quality of the product is 5g/m ² and has good water resistance.

Example 4

Raw material: bleached wheat straw pulp, beating degree 34°SR. The waste expanded polystyrene foam particles have a density of 0.03g/cm ³ , and the particle size after crushing is 0.3 mm to 0.5 mm. The binder is carboxymethyl cellulose and polyvinyl alcohol. The water repellant is melamine formaldehyde resin.

Preparation steps and product performance:

First, 100 parts of bleached wheat straw pulp are uniformly dispersed in 1000 parts of water under stirring, which is equivalent to a pulp concentration of 10%. Then add 100 parts of expanded polystyrene plastic particles, 5 parts of carboxymethyl cellulose, 10 parts of polyvinyl alcohol, 20 parts of melamine formaldehyde resin, and disperse evenly to obtain bleached wheat straw pulp, expanded polystyrene plastic particles, Suspension mixture of carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin and water.

Pour the above mixture into a mold with a filter screen, close the mold, and squeeze the filter screen, and the mixture sandwiched between the two filter screens is dehydrated on both sides under pressure to obtain pulp containing bleached wheat straw with a pulp water content of 50%. , a wet solid mixture of expanded polystyrene plastic particles, carboxymethyl cellulose, polyvinyl alcohol, and melamine formaldehyde resin.

Put the above-mentioned wet solid mixture into another mold, dry in an oven at a drying temperature of 100°C, and perform hot pressing in a hot press at a temperature of 125°C to 150°C to obtain bleached wheat straw Cushioning packaging materials for pulp and expanded polystyrene foam waste. The product has a density of 0.65g/cm ³ and good cushioning performance; the surface water absorption quality of the product is 5g/m ² and has good water resistance.

Example 5

Raw material: deinked waste paper pulp, beating degree 37°SR. The waste expanded polystyrene foam particles have a density of 0.03g/cm ³ , and the particle size after crushing is 0.3 mm to 0.5 mm. The binder is carboxymethyl cellulose and polyvinyl alcohol. The water repellant is melamine formaldehyde resin.

Preparation steps and product performance:

First, 100 parts of bleached wheat straw pulp are uniformly dispersed in 1000 parts of water under stirring, which is equivalent to a pulp concentration of 10%. Then add 100 parts of expanded polystyrene plastic particles, 5 parts of carboxymethyl cellulose, 10 parts of polyvinyl alcohol, and 20 parts of melamine formaldehyde resin, and disperse evenly to obtain a mixture containing deinked waste paper pulp and expanded polystyrene plastic particles. , carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin and water suspension mixture.

Pour the above mixture into a mold with a filter screen, close the mold, and squeeze the filter screen, and the mixture sandwiched between the two filter screens is dehydrated on both sides under pressure to obtain deinked waste paper pulp, expanded polystyrene Wet solid mixture of plastic granules, carboxymethyl cellulose, polyvinyl alcohol, melamine formaldehyde resin.

Put the above-mentioned wet solid mixture into another mold, dry in an oven at a drying temperature of 100°C, and perform hot-press setting in a hot press with a hot-press setting temperature of 125°C to 150°C to obtain deinked Cushioning packaging materials for waste paper pulp and expanded polystyrene foam waste. The product has a density of 0.59g/cm ³ and good cushioning performance; the surface water absorption quality of the product is 5g/m ² and has good water resistance.

The above examples show that according to the method of the present invention, the material comprising plant fibers and waste expanded polystyrene foam particles has a relatively low density, good cushioning performance, and good water resistance, and its performance is between that of pulp molded plastics. Between plastic products and foamed plastic products, it can be used as a cushioning packaging material in the packaging field.

At the same time, the invention makes full use of plastic packaging waste, which is beneficial to eliminate the environmental pollution caused by foamed plastics, and is also a way to effectively recycle and reuse packaging waste.

Those skilled in the art should understand that the above-mentioned preferred embodiments are only specific descriptions of the present invention, and do not constitute limitations to the present invention. Various improvements, combinations, subcombinations, and transformations can be made thereon as required, and all improvements, combinations, subcombinations, transformations, and equivalent replacements fall within the scope of the appended claims.

Claims (3)

1. A method for preparing a water-resistant cushioning packaging material containing plant fibers and foamed plastic waste, characterized in that the composition includes 50-100 parts by mass of plant fibers, 50-100 parts by mass of waste expanded polystyrene plastics Particles, 10-25 parts by mass of binder and 10-25 parts by mass of water-resistant agent; the particle size of expanded polystyrene plastic particles is between 0.3 and 1.0 mm; the binder is carboxymethyl cellulose or At least one of the polyvinyl alcohol, the water-resistant agent is urea-formaldehyde resin or melamine-formaldehyde resin; comprising the following steps: (1) A mixture of plant fibers and waste expanded polystyrene plastic particles Under the action of stirring, disperse the solid plant fiber in the water, the mass percentage concentration of the plant fiber is 10%-20%, then add the waste expanded polystyrene particles, add the binder and the water-resistant agent in turn, and stir and mix evenly; (2), dehydration and forming Pour the above mixture into a mold with a filter, close the mold, and squeeze the filter. The mixture sandwiched between the two filters is dehydrated on both sides under pressure, and the water in the mixture is removed through the filter. , to obtain a mixed material containing plant fibers and waste foamed plastic particles, a binder and a water-resistant agent, the mixed material is in a wet solid state; (3), drying and shaping The mixed material obtained in step (2) is placed in a mold, dried in an oven at a drying temperature of 100°C, and hot-pressed in a hot press at a temperature of 125°C to 150°C to obtain a mold Shaped cushioning wrapping material. 2. according to the method for claim 1, it is characterized in that, the mass percent composition of carboxymethyl cellulose in binder is not higher than 50%. 3. according to the method for claim 1, it is characterized in that, the mass percent composition of carboxymethyl cellulose in binder is 30%～50%.