An Insight into the Growing Concerns of Styrene Monomer and Poly(Styrene) Fragment Migration into Food and Drink Simulants from Poly(Styrene) Packaging

Poly(styrene) (PS) has been heavily utilised in disposable food packaging due to its insulating properties, optical translucency, and long-shelf life. Despite these desirable characteristics, (PS) poses toxicity concerns to human’s health through styrene monomer leaching into foodstuffs. Environmental and marine hazards are another growing concerns due to improper and/or absence of recycling strategies and facilities. This preliminary work aims to investigate the effect of temperature, food composition and contact times on the migration of the styrene monomer from poly(styrene) food contact materials into food simulants. Poly(styrene) cups showed a relatively low level of styrene migration with the highest being 0.110 µg/mL, whereas food containers showed a much higher level of styrene leaching with up to 6 µg/mL. This could be due to an increase in the hydrophobicity of the simulants’ characteristics from low to high fat content and the increase in the testing temperatures from 5 °C to 70 °C. ANOVA statistical analysis is used to compare the means of three or more groups of data, whereas t-test analysis is used to compare means of two groups. This was carried out on each individual sample to determine the significance of changing the temperature, simulant type, or both on the level of migration observed in the results. All significant values were tested at 95% confidence level p < 0.05, concluding that fat content and high temperatures were found to significantly increase the level of styrene migration. Nile Red staining method was used to demonstrate that particulate poly(styrene), as well as styrene monomer, migrated into tested food simulants from typical containers, which is becoming a cause for concern as evidence of microplastic ingestion increases.

Effect of Polymer Viscosity and Polymerization Kinetics on the Electrical Response of Carbon Nanotube Yarn/Vinyl Ester Monofilament Composites

The effect of polymerization kinetics and resin viscosity on the electrical response of a single carbon nanotube yarn (CNTY) embedded in a vinyl ester resin (VER) during polymerization was investigated. To analyze the effect of the polymerization kinetics, the concentration of initiator (methyl ethyl ketone peroxide) was varied at three levels, 0.6, 0.9, and 1.2 wt.%. Styrene monomer was added to VER, to reduce the polymer viscosity and to determine its effect on the electrical response of the CNTY upon resin wetting and infiltration. Upon wetting and wicking of the CNTY by VER, a transient decrease in the CNTY electrical resistance (ca. −8%) was observed for all initiator concentrations. For longer times, this initial decrease in electrical resistance may become a monotonic decrease (up to ca. −17%) or change its trend, depending on the initiator concentration. A higher concentration of initiator showed faster and more negative electrical resistance changes, which correlate with faster gel times and higher build-up of residual stresses. An increase in styrene monomer concentration (reduced viscosity) resulted in an upward shift of the electrical resistance to less negative values. Several mechanisms, including wetting, wicking, infiltration, electronic transfer, and shrinkage, are attributed to the complex electrical response of the CNTY upon resin wetting and infiltration.

Consequences of Styrene monomer leakage into the atmosphere- a damage to the human beings in the world

India has been facing many problems in recent times due to pandemic Covid-19, pollution, population and also many other natural disasters. In addition to these problems, the country is also facing some tragedies such as leakage of gases from industries and blasts. Many gas leakages and blasts were seen in India from the last few decades. Recently, the Visakhapatnam in Andhra Pradesh, India also experienced a gas leakage into atmosphere, which is a dangerous chemical gas i.e styrene from Polymer Company named LG polymer India Company limited on May 7th 2020. LG polymers manufacture plastics and expandable plastics using styrene monomer as raw material. Many people were affected and died due to this leakage of dangerous chemical gas which was released from the polymer industry at early hours of morning. The gas leakage has spread to many nearby villages and has spread to many kilometres. Mainly respiratory problems, eye irritation and skin irritation are the symptoms of the exposure to styrene. Long exposure to this chemical gas may cause the respiratory diseases that effect during lifetime. There should be some environmental measurements and remedies should be taken by government and also by the people in order to overcome these types of situations.

Styrene Monomer Migration from Expanded Polystyrene Into Food Acids and Ethanol

Migration of styrene monomer from expanded polystyrene (EPS) at various time intervals (3 hr, 1, 2, 3, 5, 7, 9, 12, 18 days at 51OC) into nine different stimulants (water, 8% ethanol in water, 3% acetic acid, and 3 and 10% of food-grade citric, malic and tartaric acid) was determined using a modified FDA migration cell. Exposure to 8% ethanol resulted in the greatest average migration of styrene (147.6 &micro;g/L) during 18 days of storage compared to all other stimulants tested. The concentration for styrene in 8% ethanol ranged from 49.3 to 228.5 &micro;g/L over all exposure times. For all stimulants tested, styrene concentrations were greater than or equal to 22 &micro;g/L after 3 hours of exposure. EPS exposed to malic (3 and 10%) and 10% tartaric acids had greater styrene migration than styrene exposed to all other acidic stimulants tested.

Synthesis of Nixantphos Core-Functionalized Amphiphilic Nanoreactors and Application to Rhodium-Catalyzed Aqueous Biphasic 1-Octene Hydroformylation

A latex of amphiphilic star polymer particles, functionalized in the hydrophobic core with nixantphos and containing P(MAA-co-PEOMA) linear chains in the hydrophilic shell (nixantphos-functionalized core-crosslinked micelles, or nixantphos@CCM), has been prepared in a one-pot three-step convergent synthesis using reversible addition-fragmentation chain transfer (RAFT) polymerization in water. The synthesis involves polymerization-induced self-assembly (PISA) in the second step and chain crosslinking with di(ethylene glycol) dimethacrylate (DEGDMA) in the final step. The core consists of a functionalized polystyrene, obtained by incorporation of a new nixantphos-functionalized styrene monomer (nixantphos-styrene), which is limited to 1 mol%. The nixantphos-styrene monomer was synthesized in one step by nucleophilic substitution of the chloride of 4-chloromethylstyrene by deprotonated nixantphos in DMF at 60 °C, without interference of either phosphine attack or self-induced styrene polymerization. The polymer particles, after loading with the [Rh(acac)(CO)2] precatalyst to yield Rh-nixantphos@CCM, function as catalytic nanoreactors under aqueous biphasic conditions for the hydroformylation of 1-octene to yield n-nonanal selectively, with no significant amounts of the branched product 2-methyl-octanal.