The Impact of AN Contribution on the Thermal Characteristics and Molecular Dynamics of Novel Acrylonitrile–Styrene–Styrene Sodium Sulfonate Terpolymers

We performed a free radical solution polymerization of new acrylonitrile (AN), styrene (St) and styrene sodium sulfonate (SSS) acceptor–donor acceptor monomer systems. The compositions and structures of the produced terpolymers were elucidated using CHNS elemental analysis, and Fourier transform infrared (FTIR) spectroscopies. Three terpolymers candidates were chosen for detailed thermal investigations, where the AN molar ratio varied almost threefold (from ~6.9% to ~17.4%) while the molar ratios of St and SSS varied slightly, at average values around 76.0% and 12.9%, respectively. The glass transition (Tg) values of the terpolymers were measured calorimetrically. In addition, thermal gravimetric analyses (TGA) of the samples were conducted in the temperature range from room temperature to 800 °C. All terpolymers exhibited a single Tg value, indicating random copolymerization of the monomeric species. TGA results revealed that variation of the AN molar ratio had a significant influence on the thermal stabilities of the terpolymers. The impact of AN contribution on the molecular dynamics of the glass transition in the terpolymers was explained quantitatively in a framework of a molecular model

The Impact of AN Contribution on the Thermal Characteristics and Molecular Dynamics of Novel Acrylonitrile–Styrene–Styrene Sodium Sulfonate Terpolymers

We performed a free radical solution polymerization of new acrylonitrile (AN), styrene (St) and styrene sodium sulfonate (SSS) acceptor–donor acceptor monomer systems. The compositions and structures of the produced terpolymers were elucidated using CHNS elemental analysis, and Fourier transform infrared (FTIR) spectroscopies. Three terpolymers candidates were chosen for detailed thermal investigations, where the AN molar ratio varied almost threefold (from ~6.9% to ~17.4%) while the molar ratios of St and SSS varied slightly, at average values around 76.0% and 12.9%, respectively. The glass transition (Tg) values of the terpolymers were measured calorimetrically. In addition, thermal gravimetric analyses (TGA) of the samples were conducted in the temperature range from room temperature to 800 °C. All terpolymers exhibited a single Tg value, indicating random copolymerization of the monomeric species. TGA results revealed that variation of the AN molar ratio had a significant influence on the thermal stabilities of the terpolymers. The impact of AN contribution on the molecular dynamics of the glass transition in the terpolymers was explained quantitatively in a framework of a molecular model

Assessment of Primary Care Physicians’ Expertise of Common Dermatological Conditions in the Jouf Region, Saudi Arabia: A Mixed Methods Study

Primary care physicians (PCPs) are the first line of defense for the management of common dermatological conditions (DCs). This study aimed to assess how dermatological diseases are identified, managed, and referred to in primary healthcare centers (PHCs). This was a mixed methods study comprising a cross-sectional survey and semi-structured interviews recruited through PHCs across the Jouf region of Saudi Arabia. Sixty-one PCPs completed the data, and eight participants were interviewed. A survey based on a sample of 22 photographs of common DCs in the Kingdom was administered to the participants to answer questions about the correct diagnosis, appropriate management, referral strategy, and encounter rate. In our sampled population, the mean overall knowledge level on a scale of 10 was 7.08 (±1.3). Among participants that had good to acceptable scores, 51 (83.6%) were in the overall knowledge parameter, 46 (75.4%) in the diagnosis parameter, and 49 (80.3%) in the management parameter. PCPs with five years or more of experience were found to have significantly higher overall knowledge and management scores. Most of our PCPs demonstrated sufficient knowledge of common DCs and had good to acceptable scores in all parameters. However, educational and regulatory aspects of PCPs’ clinical management were identified. Focused training, provision of workshops, and improving medical school curricula regarding common DCs are recommended