Study on the migration of PLA food packaging additives: simulation of the interaction between food simulant diffusion, solvent induced crystallization, and plasticizer consumption

Research focuses on additive migration in PLA packaging. A study titled “Additive migration from poly (lactic acid) packaging: Modeling the interplay between food simulation diffusion, solution induced polymer crystallization, and plasticizer depletion” was published in Volume 58 of Food Packaging and Shelf Life (December 2026) by Ali Ghasemi, Marina Tsianou, and Paschalis Alexandris. The study focuses on polylactic acid (PLA) packaging and investigates the interactions between food simulant diffusion, solvent induced polymer crystallization, and plasticizer consumption during the migration of additives to food simulants through modeling.

PLA, as a bio based biodegradable resin, has attracted attention in the film, container and other scenarios of food and daily chemical packaging.

. Compared with conventional polyolefins, PLA may undergo more significant structural changes when in contact with food simulants, which makes the migration behavior of additives no longer just a simple diffusion problem, but involves the process of polymer matrix state evolution with contact time.

The coupling of the three processes is key to understanding migration

According to the framework revealed in the research title, additive migration is influenced by three clues:

• Diffusion of food simulants: simulants penetrate into the interior of the polymer, change the matrix environment, and provide channels for additive migration;

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• Solvent induced polymer crystallization: Simulating substances may induce changes in crystallization behavior when in contact with PLA, thereby altering the activity and free volume of polymer segments and affecting migration pathways.

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• Plasticizer consumption: Plasticizers are gradually consumed or precipitated during contact, causing material properties and migration driving forces to change over time.

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Research describes the mutual coupling of the above processes in a modeling manner, rather than evaluating a single factor in isolation. This approach suggests that in packaging material design, migration assessment needs to consider dynamic changes on the contact time scale, rather than relying solely on static parameters of the initial formulation.

Significance for the polymer additive industry

For enterprises engaged in the development of packaging materials and additives, this study provides several perspectives worth paying attention to.

. Firstly, in the compliance assessment of food contact, the migration behavior of bio based resins such as PLA may change with the penetration and crystallization changes of simulants. The selection and dosage design of additives need to be considered together with the evolution process of the matrix. Secondly, the formulation design of processing stability and additives such as antioxidants should not only meet the thermal stability requirements during the processing stage, but also evaluate their migration tendency under contact conditions; For plasticizer systems, the dynamic processes of consumption and precipitation should be incorporated into the migration model. Again, with the increasing application of recycled materials in packaging, the structural heterogeneity and residual additives that recycled materials may bring will also make migration behavior more complex. Modeling evaluation methods have reference value. It should be noted that this study focuses on modeling, and the abstract information does not provide specific migration data, experimental system details, or conclusion values. Therefore, it is not appropriate to infer the migration level of specific additives or formulations based on this. Its value lies more in proposing a methodological framework that couples diffusion, crystallization, and plasticizer consumption analysis, providing ideas for material screening and migration testing design in subsequent food contact packaging.

Source: Food Packaging and Shelf Life, Volume 58, December 2026; Author: Ali Ghasemi, Marina Tsianou, Paschalis Alexandridis.

Information source:Additive migration from poly(lactic acid) packaging: Modeling the interplay between food simulant diffusion, solvent-induced polymer crystallization, and plasticizer depletion， Organized by Herun Chemical.