Novel Method for Visualizing Water Transport Through Phase-Separated Polymer Films

AbstractDrug release from oral pharmaceutical formulations can be modified by applying a polymeric coating film with controlled mass transport properties. Interaction of the coating film with water may crucially influence its composition and permeability to both water and drug. Understanding this interaction between film microstructure, wetting, and mass transport is important for the development of new coatings. We present a novel method for controlled wetting of polymer coating films in an environmental scanning electron microscope, providing direct visual information about the processes occurring as the film goes from dry to wet. Free films made of phase-separated blends of water-insoluble ethyl cellulose (EC) and water-soluble hydroxypropyl cellulose (HPC) were used as a model system, and the blend ratio was varied to study the effect on the water transport properties. Local variations in water transport through the EC/HPC films were directly observed, enabling the immediate analysis of the structure–mass transport relationships. The leaching of HPC could be studied by evaporating water from the films in situ. Significant differences were observed between films of varying composition. The method provides a valuable complement to the current approach of making distinct diffusion and microscopy experiments for studying the dynamic interaction of polymer films with water.

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Monitoring of polymer type and plastic additives in coating film of beer cans from 16 countries

Scientific Reports ◽

10.1038/s41598-021-01723-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nurlatifah ◽

Haruhiko Nakata

Keyword(s):

Polymeric Coating ◽

Coating Film ◽

Chemical Additives ◽

Coating Films ◽

Metal Debris ◽

Potential Source ◽

Detection Frequency ◽

Apparent Relationship ◽

Lower Detection ◽

Almost All

AbstractPlastic debris has gained attention as anthropogenic waste in the environment, but less concerned given to metal waste despite its high abundance in aquatic environment. Metal packaging, such as can, utilizes polymeric coating films as barrier between metals and products which leads to be potential source of microplastic pollution. In this study, 27 beer cans from 16 countries for both body and lid parts as well as inside and outside layers were investigated. Despite the country’s origin, epoxy resin was the major polymeric coating used in all beer cans for lid (inside and outside) and body (inside). Whereas poly(1,2-butanediol isophthalate) was frequently used for outside layer of can body. DEHP and BHT were detected in almost all samples with the highest concentration of 5300 ng/g and 520 ng/g. Despite its lower detection frequency, DOA was detected as high as 9600 ng/g in Belgian beer can. There was no apparent relationship present between the home countries of beer cans and amount of additives used. Despite of being broken down, additives concentration in one environmental sample was found to be one to two orders of magnitude higher compared to the new can. This result proved that adsorption of chemical additives took place in the environment and degraded metal debris may become source of microplastic with higher risk of additives pollution in the environment.

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Correlating 3D porous structure in polymer films with mass transport properties using FIB-SEM tomography

Chemical Engineering Science X ◽

10.1016/j.cesx.2021.100109 ◽

2021 ◽

pp. 100109

Author(s):

C. Fager ◽

T. Gebäck ◽

J. Hjärtstam ◽

M. Röding ◽

A. Olsson ◽

...

Keyword(s):

Mass Transport ◽

Porous Structure ◽

Transport Properties ◽

Polymer Films

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Monitoring of Polymer Type and Plastic Additives in Coating Film of Beer Cans From 16 Countries

10.21203/rs.3.rs-820486/v1 ◽

2021 ◽

Author(s):

Nurlatifah ◽

Haruhiko NAKATA

Keyword(s):

Polymeric Coating ◽

Coating Film ◽

Coating Films ◽

Metal Debris ◽

Plastic Debris ◽

Potential Source ◽

Detection Frequency ◽

Lower Detection ◽

Almost All ◽

Polymer Type

Abstract Plastic debris has gained attention as anthropogenic waste in the environment, but less concerned given to metal waste despite its high abundance in aquatic environment. Metal packaging, such as can, utilizes polymeric coating films as barrier between metals and products which leads to be potential source of microplastic pollution. In this study, 27 beer cans from 16 countries for both body and lid parts as well as inside and outside layers were investigated. Despite the country’s origin, epoxy resin was the major polymeric coating used in all beer cans for lid (inside and outside) and body (inside). Whereas poly(1,2-butanediol isophthalate) was frequently used for outside layer of can body. Marketing countries turned out not specify the amount of additives used in can. DEHP and BHT were detected in almost all samples with the highest concentration of 5,300 ng/g and 520 ng/g. Despite its lower detection frequency, DOA was detected as high as 9,600 ng/g in Belgian beer can. Although being broken down, additives concentration in one environmental sample was found to be one to two orders of magnitude higher compared to the new can. This result suggests that metal debris may become source of microplastic and additives in the environment.

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