Perilaku Slow-Release Fertiliser pada Membran Nanofiber Poly(vinyl) Alcohol (PVA)/Urea/TiO2

Nadiisah Nurul Inaayah, Dr. Eng. Ahmad Kusumaatmaja, S.Si., M.Sc.

2023 | Tesis | S2 Ilmu Fisika

Pembuatan slow-release nanofiber PVA/Urea/TiO2¬ telah berhasil dilakukan dengan metode fabrikasi electrospinning. Membran slow-release PVA/Urea/Tio2, dibuat dengan variasi konsentrasi larutan suspensi TiO2 (0; 0,2; 0,4mL) dan variasi massa urea (10,15 dan 20% terhadap massa PVA). Masing-masing sampel kemudian dikarakterisasi menggunakan SEM dan FTIR, serta diuji dengan uji sudut kontak dan uji slow-release. Seluruh sampel menunjukan dapat membentuk nanofiber, serta terdapat gugus nitrogen pada matriksnya. Keberdaan TiO2 dikonfirmasi dengan citra SEM Mapping. Data hasil uji sudut kontak menunjukan kesemua sampel bersifat hidrofilik (sudut kontak kurang dari 90o). Uji slow -release menggunakan metode relasi absorbansi dan konsentrasi berdasarkan hukum Lambert-Beer, ditemukan bahwa sampel dengan variasi urea terbanyak (0,4mL) memiliki waktu release urea yang paling lama yakni 8 hari menunjukan sifat hidrofobik urea yang dapat menekan hidofilitas membran PVA, serta penambahan urea menambah hidrofilitas membran yang mempercepat laju release. Berdasarkan model kinetik matematis Korsmeyer-Peppas didapatkan mekanisme drug-release dari membran dipicu fenomena erosi pada badan matriks nanofiber.

Slow-release PVA/Urea/TiO2 nanofibers have been successfully fabricated using the electrospinning fabrication technique. Different urea mass concentrations (10.15 and 20% of PVA mass) and titanium dioxide suspension solution concentrations (0, 0.2, and 0.4 mL) were used to make PVA/Urea/TiO2 slow-release membranes. Following that, each sample was examined using SEM and FTIR characterisation and assessed using a contact angle test and a slow-release test. All samples showed nanofiber formation capability, and the matrix contained nitrogen groups. The presence of titanium dioxide was confirmed by the SEM mapping pictures. The results of the contact angle test indicated that all samples were hydrophilic (contact angle less then 90o). The sample with the highest urea variation (0.4 mL) was found to have the longest urea release period, which was 8 days, descriptive of urea's hydrophobic character, which could inhibit the hydrophilicity of the PVA membrane. Urea will make the membrane more hydrophilic, which quickens the rate of release. Based on the Korsmeyer-Peppas mathematical kinetic model, it was determined that the drug-release mechanism from the membrane is driven by erosion processes on the nanofiber matrix body.

Kata Kunci : Slow-Release Fertilizer, Nanofiber, PVA/ TiO2/ Urea, Elektrospining