Under the continuous promotion of plastic restriction and plastic ban policies, pulp molded products and PLA (polylactic acid).and other degradable plastic products have ushered in vigorous development. The main advantages and disadvantages of pulp molded products compared to degradable plastic products such as PLA (polylactic acid) are as follows:
(1) Degradability
Pulp molded products are also known as "plant fiber molded products", and the raw materials are mainly bagasse pulp, bamboo pulp, wood pulp and other natural plant fibers. After the plant fibers are compressed by molds, they can be made into a variety of products with different shapes and different uses. Only physical changes occur in the production process of the product, there is no chemical change, and the product can be naturally degraded in the natural environment without special treatment after use, and finally decomposed into water and carbon dioxide.
PLA (polylactic acid) is a bio-based chemical polymer, the upstream raw material is mainly lactic acid, and the upstream raw material of lactic acid is mainly starch. PBAT is a petroleum-based degradable material, which is chemically synthesized with aliphatic acid and butylene glycol as raw materials, both of which can be biodegraded under specific conditions, and finally decomposed into water, carbon dioxide, etc.
The comparison of the degradability of pulp molded products and PLA and PBAT products is as follows:
Note 1: Natural degradation means that after the product is discharged into nature, it will decompose into non-toxic and harmless ingredients that already exist in nature after a few months;
Note 2: Industrial composting is a process in which microorganisms degrade solid and semi-solid organic matter aerobically at medium or high temperature under controlled conditions to produce stable humus, with a general cycle of 180 days
Note 3: Home composting is the process of aerobic composting using household food waste or garden waste for the production of compost for home use. The time taken for home composting is longer than that for industrial composting, but generally not more than one year;
Note 4: Refer to the relevant research reports of Hua'an**, Dongfang**, and Dongxing**.
Since the raw materials themselves are derived from natural plant fibers, pulp molded products can be naturally degraded after being buried in the soil. In contrast, PLA is subject to more demanding degradation conditions, requiring high temperature and humidity and a large number of microorganisms, and it can take up to six months to show signs of degradation even when buried deep in the soil, and industrial composting is required.
PBAT's degradation conditions are slightly lower than PLA's, but composting conditions are still required to ensure a rate of degradation. However, industrial composting requires a supporting garbage treatment system, which has relatively high requirements, such as the separate sorting of degradable plastic products at the front end, and the investment and construction of industrial composting facilities, which are costly. Both PLA and PBAT are difficult to degrade in the natural environment.
In summary, the degradation conditions required for pulp molded products are simpler, the degradation cost is lower, and the natural total degradability is much better than that of degradable plastic products such as PLA (polylactic acid).
(2) Product performance and application field
Compared with PLA PBAT degradable plastic products, pulp molded products are at a relative disadvantage in terms of product performance, barrier and transparency, but they are not inferior to PLA PBAT degradable plastic products in terms of applicable temperature range and molding performance. In particular, due to its poor resistance to high temperatures, PLA materials will decompose and deform at temperatures higher than 50 or when they are enriched with oxygen and microorganisms. As a result, PLA related products need to be insulated during transportation, and the storage requirements are also high, and the application in the field of tableware is relatively limited, and related products cannot be microwaved heated.
In summary, pulp molded products have advantages and disadvantages in different application fields due to certain differences in applicable temperature range, barrier and transparency, etc., compared with other degradable materials such as PLA (polylactic acid). Pulp molded products are mainly used in cushioning packaging and tableware, while other degradable materials such as PLA (polylactic acid) are mainly used in film bag packaging and specific fields of tableware (such as straws, cups, knives, forks and spoons, etc.).
(3) Raw material cost and product**
During the reporting period, the market of bagasse pulp, the main raw material of domestic pulp molding products, was quite different from PLA and PBAT, and the unit cost of bagasse pulp was much lower than that of PLA and PBAT.
Because the raw material cost of pulp molded products is much lower than that of PLA PBAT, pulp molded products are typically sold at a lower price per weight than degradable plastic products such as PLA PBAT. Pulp molded products are more competitive in the first place.