With the escalation of global environmental awareness and tightening of policies, the green transformation of the plastic hollow product industry is accelerating, making the recycling and utilization of PCR recycled plastics a crucial aspect. However, in practical production, there are often numerous challenges when using HDPE to manufacture hollow products.

Question:

① Appearance defects, such as black spots, impurities, and color deviations;

② Insufficient process stability, such as unstable glue flow;

③ Performance degradation, such as decreased drop strength and stacking performance.

PCR (post-consumer recycled material) serves as a pivotal carrier in the circular economy, having achieved large-scale application in multiple fields, demonstrating notable environmental benefits and resource recycling value. In recent years, with the accelerated green transformation of MEPER BLOW MOLDING, the addition of PCR to common substrates such as PP and HDPE has become a standard industry practice. Despite its widespread application, PCR materials still encounter dual bottlenecks in technology and market, hindering their large-scale penetration.

Appearance defects (such as black spots, impurities, and color deviations) and performance degradation are the most common product issues encountered when PCR materials are applied to hollow products.

The reasons for these issues are as follows:

(1) Complex source of raw materials: PCR materials (especially those from post-consumer recycling) may contain residual labels, glue, plastics of different colors, and non-plastic impurities (such as paper, metal shavings). If not completely removed during cleaning and sorting, they may carbonize and form black spots and yellow streaks after high-temperature processing.

(2) Processing performance fluctuation: PCR materials have undergone at least one processing lifecycle (use-recycling-reprocessing), during which the polymer chains may undergo breakage or crosslinking, leading to a broader molecular weight distribution and reduced structural uniformity. This affects processing stability, posing challenges especially for high-precision injection-blow molding products.

(3) Material cost pressure: The price of high-quality PCR is often higher than that of new materials, primarily due to the high costs associated with recycling, sorting, impurity removal, and modification, as well as the difficulty in achieving economies of scale. There exists a contradiction between the cost-reduction needs of end-user enterprises and the advocacy for green and sustainable development.