Application of Paper Fiber Green Packaging Materials

With the rapid development of industry, the demand for packaging materials is increasing, especially packaging materials with cushioning functions, such as plastic foam materials, occupy a pivotal position in the past 20 years. However, due to the long-term non-biodegradability of plastic foam material waste in the natural world, causing serious "white pollution" to the environment, has been banned from use in many countries, China will gradually ban the use of. Plant fiber materials have a long history. Wood and carton are all traditional plant fiber packaging materials. However, as a packaging material with buffer function, the physical and mechanical properties cannot be compared with foam plastic products. The plant fiber bulking packaging material has the characteristics of natural degradation, reusability, reproducibility, and extensive resources, as well as light weight, impact resistance, thermal insulation, sound absorption, and shock proof of plastic foam packaging materials. Features. Plant fiber bulking packaging materials will not only bring about a revolution in the field of packaging materials, but also expand the space for the application of plant fibers. Buffer packaging material is a kind of disposable packaging that has a short life cycle and is “used and thrown”. The negative impact on the environment is obvious. Green buffer packaging material is the inevitable trend of buffer packaging material development [1]. The State Bureau of Technical Supervision has set standards for the selection, processing, and application of green packaging materials, including five products: pulp, paperboard coatings, biodegradable plastics, starch, and vegetable fibers.

1 Characteristics of Natural Plant Fibers

Natural plant fibers such as bagasse, cotton stalks, husks, corn stalks, rice straw, wheat straw, etc., are a kind of renewable natural resources rich in resources. According to the survey, China's annual crop straw is more than 200 million tons. Plant straws have many advantages as packaging materials, such as good buffering performance, non-toxic, odorless, good ventilation performance, and completely natural degradation after use. Paper materials are the most familiar and widely used green packaging materials [2]. They have a wide range of raw materials. Waste can be used to recycle recycled paper and is easily corrupted in the natural environment. It is the earliest green packaging material. In the 1990s, people in the materials industry proposed "to replace paper with plastic." Typical varieties currently widely used for packaging are pulp molding and honeycomb paperboard products. In particular pulp molded products are used to replace refractory foam plastics and are widely used in tableware and poultry egg trays, fruit trays, industrial trays, food and semi-finished product packaging, and medical device packaging. Northwest Agricultural University of China has conducted a lot of research in this area, researching and developing fruit and vegetable packaging linings, poultry egg trays, supermarket trays, corrugated paper, disposable tableware and other products. Its production process has matured and will soon be brought to market in large quantities. Although paper has many advantages, there are also many shortcomings: papermaking consumes a lot of wood and causes water pollution at the same time; papermaking costs are high, and the mechanical strength and water resistance of paper are also difficult to compare with plastics. This shows that green packaging materials also have the characteristics of the times. Only in the fiber processing technology work hard, the use of fiber products will be more extensive, its huge potential to get the proper play.

2 types of paper-based packaging materials

2. 1 shredded paper

Shredding is an economical and readily available cushioning material. It is affected by water and can retain moisture due to siphon action. It does not prevent the item from sinking into contact with the container, so it can only be used on light and small items. Shred paper is flammable and may ignite spontaneously under certain conditions.

2. 2 crepe paper

Crepe paper is an economical and easily available cushioning material. It is characterized by its stable surface properties, low dust generation, easy processing, and good plasticity. Its cushioning effect is mainly achieved by the extrusion of crepe paper and can provide light interior products. Good buffer effect.

2. 3 paper pad paper

The paper pad is divided into two types, a thin pad and a felt pad. The thin paper pad is composed of several thin papers, up to 10 thin papers; the felt paper pad is made of pulp and used as a buffer packaging material, mainly a thin paper pad. The paper pad is soft, does not damage the surface of the product, has good air permeability, easily emits harmful gas or moisture, has low cost, and has good processing performance. The disadvantage is that it is easy to generate dust and poor water resistance. Paper pad is widely used for surface protection of furniture, musical instruments, household appliances and other products.

2. 4 Fiberboard

Fiberboard, also known as paper fiber molding material, is a kind of elastic buffer packaging material made of waste pulp, slurry, etc. It can be pressed into single-sided corrugated cardboard, or it can be made into soft and elastic thick paper. Some fiberboards can also be waterproofed, or affixed with kraft paper, lining and other surface treatment, so as to obtain better surface properties. Fiberboard is widely used as wrapping materials, cushioning materials and construction materials.

2. 5 corrugated cardboard

Corrugated board [3 - 4 ] is made of kraft paper (boardboard) as the inner surface and corrugating medium (corrugated paper) as the core. Different types of corrugated cardboard can be obtained by changing the number of layers of paper in the core and the shape and size of the corrugated medium. It has the advantages of good environmental protection performance, wide application temperature range, low cost, convenient material acquisition, mature production process, and good processing performance. The disadvantages are poor flexibility and poor resilience. For the contents, three or five layers of corrugated cardboard can be used directly as the cushion for the inner package. At the same time, corrugated board can be made into various shapes of gaskets, gaskets, spacers, liners, corner guards and guard edges. For example, a new type of composite board made of corrugated paperboard and multi-layer paper core successfully developed by China Agricultural University's Institute of Resources and Environment has been successfully applied to the production of container pallets. The new type of corrugated cardboard has high compressive strength and good cushioning performance. Its packaging cost is lower than that of wooden boxes and lighter than wood products. The multi-layer paper core composite board not only has strong bending resistance, but also has characteristics such as flame retardant, water resistance, light weight, heat preservation, and sound insulation after special treatment. Both of these patented products are based on waste paper as the main raw material, processing is convenient, production costs are low, the production process is non-polluting, waste products can be recycled, environmental protection and price advantages, widely used in electronic and fruit products such as the buffer On the packaging.

Corrugated board is widely used in packaging due to its advantages of no pollution, renewable, good cushioning properties, etc. In 1871, the American (Albert Jones) invented single-sided corrugated cardboard for packaging glass shades and similar fragile items and obtained the first US patent. By the end of the 19th century, the United States began to study the use of corrugated cardboard for packaging and transportation. The box and the Japanese invention of double corrugated cardboard in 1920, its use in the rapid expansion of the world, to World War II, corrugated boxes have replaced wooden boxes in transport packaging accounted for 80%, so far, corrugated board has As one of the most widely used packaging materials in modern packaging, the output value of corrugated cartons accounted for more than 30% of the total output value of packaging industry products. China's corrugated paper box industry started relatively late. In 1954, it began to promote the use of corrugated boxes, and its technology starting point was low. Since its opening, China's corrugated paper box industry has developed rapidly. There are more than 2,000 corrugated production lines in the Pearl River Delta, Yangtze River Delta and coastal economically developed regions. Almost all of the corrugated board on the market is provided by the above production lines. In the 1970s and 1980s, corrugated cartons were used in China. The period of stand-alone production; the period of production of corrugated single-faced machines in the early to mid-1990s has become history, and it has been around 70-80 after the 20th century. The development has created a new era of corrugated paper box production in China. In 1995, the annual output of corrugated board in China was only 7.4 billion square meters. In 2001, the output of corrugated board in China exceeded 13 billion square meters, and in 2002 it increased by 14 billion square meters. It reached 15.1 billion square meters in 2003 and has surpassed Japan to become the world's second largest producer of corrugated board after the United States.

2. 6 Pulp Molding

Pulp molding [5-6] uses plant fibers such as waste newspapers and carton paper as the main raw materials, and it is quickly and uniformly deposited on a mesh model by vacuum molding, hydraulic modeling, and air compression molding, and molded into individual shapes. After being shaped, it is compacted and dried to maintain a constant shape of the paper product. Pulp molding began in the 1960s. China began importing pulp molding production lines from abroad in the early 1980s. It is currently the main replacement product for foams popular in domestic and foreign markets. Pulp molded products not only have abundant raw materials, low cost, high recycling rate, no environmental pollution, good plasticity and cushioning properties, light weight, low cost, shock resistance, etc., but also have good air permeability and are conducive to food seafood. The preservation of goods, in the international commodity circulation, is widely used in disposable tableware, convenient food packaging and fresh eggs, fruits, glass, ceramics, household appliances, hardware tools and other fragile products turnover packaging.

2. 7 Honeycomb Paperboard

Honeycomb paperboard [7-8] is similar to corrugated paperboard in that its paper core is not a corrugated but a honeycomb paper core. Honeycomb paperboard is a new type of packaging material developed in recent years. It has good cushioning properties, high flat compressive strength and static bending strength, excellent sound insulation and heat insulation properties, easy recycling, and low cost. The application of honeycomb paperboard in packaging mainly includes honeycomb cartons, cushion liners and honeycomb trays. Honeycomb paperboard products save resources, protect the ecological environment, and meet the development trend of international packaging industry materials. In recent years, the state has attached great importance to and supported the research, development and application of honeycomb paperboard materials. In 1999, the State Economic and Trade Commission’s Department of Resources’ research on the development countermeasures and planning of China's green packaging industry clearly identified honeycomb paperboard as an extension development plan. China National Packaging Technology Association's national "10th Five-Year Plan" packaging industry planning tasks and objectives also clearly pointed out: Export mechanical and electrical products during the "10th Five-Year" period should solve the problem of replacing wood, accelerate the research, development and application of honeycomb paperboard instead of wood. However, due to the low degree of automation in the manufacture of honeycomb paperboard, honeycomb paperboard has not been well resolved in terms of technology, process, etc., and the reasons are not high. The honeycomb paperboard products have not been widely used in the packaging industry.

2. 8 paper base cushion packaging materials

Plant fiber cushion packaging material is a new type of green environmental protection product developed in recent years. The product is made of plant fibers (waste newspapers, carton paper and other plant fiber materials) and starch addition auxiliary materials. It has the advantages of no environmental pollution, simple manufacturing process, low cost and rich raw materials. It is an ideal substitute for foam plastic packaging materials. At present, at home and abroad in the research and development of plant fiber cushion packaging materials, has achieved different degrees of progress. The process methods used in foreign plant fiber products mainly focus on adding no chemical foaming agent and foaming through the action of water vapor to form granular foamed pulp. For example, Friedrich Prius, the founder of a company in Hamburg, Germany, used waste paper and starch as raw materials to make cushioned packaging materials. Experiments show that after the buffer material is discarded, it can be quickly decomposed by microorganisms and fungi, and its performance is better than that of foam plastics. It is not only cheap, but also does not pollute the environment. The development prospect is broad; the United States natural starch and chemical company developed biodegradation. The type of buffer packaging material (referred to as ECO-FOAM) has good antistatic property and good cushioning performance, and can replace various foam plastics such as polyurethane.

Domestic plant fiber products are mainly used in the process of adding chemical foaming agents, foaming through the role of chemical foaming agents, the formation of granular foaming pulp. Due to the possible adverse effects on the environment during the production process and after use, the technology has yet to be improved and improved. For example, Tianjin University of Business School developed a new type of buffer material using crop straw crushed material and appropriate binder as raw materials; Wuhan Yuandong Green World used double-foamed plant fiber packaging material made of plant starch and high-fiber filling formula can be used for household appliances. The production enterprise replaces the foam plastic and has the advantages of moisture-proof, shockproof, compressive strength, good strength, light weight and low price. It is a new type of environmental protection packaging material.

3 Conclusion

3.1 The positive functional development trend of green packaging paper