Developing materials for use in photovoltaic (PV) systems requires knowledge of their performance over the warranted lifetime of the PV system. Poly(ethylene-terephthalate) (PET) is a critical component of PV module backsheets due to its dielectric properties and low cost. However, PET is susceptible to environmental stressors and degrades over time. Changes in the physical properties of nine PET grades were modeled after outdoor and accelerated weathering exposures to characterize the degradation process of PET and assess the influence of stabilizing additives and weathering factors. Multivariate multiple regression (MMR) models were developed to quantify changes in color, gloss, and haze of the materials. Natural splines were used to capture the non-linear relationship between predictors and responses. Model performance was evaluated via adjusted-R2 and root mean squared error values from leave-one-out cross validation analysis. All models described over 85% of the variation in the data with low relative error. Model coefficients were used to assess the influence of weathering stressors and material additives on the property changes of films. Photodose was found to be the primary degradation stressor and moisture was found to increase the degradation rate of PET. Direct moisture contact was found to impose more stress on the material than airbone moisture (humidity). Increasing the concentration of TiO2 was found to generally decrease the degradation rate of PET and mitigate hydrolytic degradation. MMR models were compared to physics-based models and agreement was found between the two modeling approaches. Cross-correlation of accelerated exposures to outdoor exposures was achieved via determination of cross-correlation scale factors. Cross-correlation revealed that direct moisture contact is a key factor for reliable accelerated weathering testing and provided a quantitative method to determine when accelerated exposure results can be made more aggressive to better approximate outdoor exposure conditions.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301690PMC
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0209016PLOS

Publication Analysis

Top Keywords

accelerated weathering
12
multivariate multiple
8
multiple regression
8
weathering exposures
8
assess influence
8
mmr models
8
degradation rate
8
rate pet
8
direct moisture
8
moisture contact
8

Similar Publications

Thermal gradient ring for analysis of temperature-dependent behaviors involving TRP channels in mice.

J Physiol Sci

January 2025

Division of Cell Signaling, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan; Thermal Biology Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Japan; Course of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan. Electronic address:

There are a lot of temperature-sensitive proteins including transient receptor potential (TRP) channels. Some TRP channels are temperature receptors having specific activation temperatures in vitro that are within the physiological temperature range. Mice deficient in specific TRP channels show abnormal thermal behaviors, but the role of TRP channels in these behaviors is not fully understood.

View Article and Find Full Text PDF

Drought-Induced Weakening of Temperature Control on Ecosystem Carbon Uptake Across Northern Lands.

Glob Chang Biol

January 2025

Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China.

Rapid warming in northern lands has led to increased ecosystem carbon uptake. It remains unclear, however, whether and how the beneficial effects of warming on carbon uptake will continue with climate change. Moreover, the role played by water stress in temperature control on ecosystem carbon uptake remains highly uncertain.

View Article and Find Full Text PDF

Background: Sesquiterpene ( +)-valencene is a characteristic aroma component from sweet orange fruit, which has a variety of biological activities and is widely used in industrial manufacturing of food, beverage and cosmetics industries. However, at present, the content in plant sources is low, and its yield and quality would be influenced by weather and land, which limit the supply of ( +)-valencene. The rapid development of synthetic biology has accelerated the construction of microbial cell factories and provided an effective alternative method for the production of natural products.

View Article and Find Full Text PDF

The main features of long-distance migration are derived from landbirds breeding in the Northern Hemisphere. Little is known about migration within the tropics, presumably because tropical species typically move opportunistically and over shorter distances. However, such generalizations are weakened by a lack of solid data on spatial, temporal and behavioural patterns of intra-tropical migrations.

View Article and Find Full Text PDF

Evidence suggests that anthropogenic climate change is accelerating and is affecting human health globally. Despite urgent calls to address health effects in the context of the additional challenges of environmental degradation, biodiversity loss and ageing populations, the effects of climate change on specific health conditions are still poorly understood. Neurological diseases contribute substantially to the global burden of disease, and the possible direct and indirect consequences of climate change for people with these conditions are a cause for concern.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!