Study of the effect of adding (TiO2) on some mechanical and thermal properties of polyvinyl chloride (PVC) pipes exposed to sunlight: no. مجلة العلوم الهندسية [Internet]. 2025 Feb. 27 [cited 2026 Jun. 18];41(1). Available from: https://journal.damascusuniversity.edu.sy/index.php/engj/article/view/7079