Preparation, Characterization And Slow-Release Properties Of Biocomposites Comprising Chitosan Encapsulated In Natural Rubber Matrices

• Main Author: Abu, Norhidayah
• Format: Thesis
• Language: English
• Published: 2016
• Subjects: QD1-999 Chemistry
• Online Access: http://eprints.usm.my/32232/1/NORHIDAYAH_BINTI_ABU_24%28NN%29.pdf; http://eprints.usm.my/32232/

Projek penyelidikan ini terdiri daripada dua bahagian. Pada bahagian pertama, kesan pH ke atas kestabilan gel chitosan berasid (CTSAc) bersama 1-Naftol (produk dilabelkan sebagai CTSAc/1-N) atau 2-Naftol (produk dilabelkan sebagai CTSAc/2-N) ditentukan. Dalam air berasid (pH ≤ 4), CTSAc/1-N atau CTSAc/2-N membentuk gel dan pecah dengan mudah. Dalam air neutral (pH ≈ 7), CTSAc/1-N dan CTSAc/2-N membentuk gel tetapi masih kelihatan utuh walaupun selepas dua minggu. Dalam air beralkali (pH ≥ 9), CTSAc/1-N dan CTSAc/2-N sukar membentuk gel walaupun selepas direndam selama tiga bulan. Selain itu, biokomposit tanpa naftol yang terdiri daripada CTSAc terkandung dalam getah asli tak tersilang ({CTSAc}NRucl) dan getah asli tersilang ({CTSAcl}NRc) disediakan. Kajian pengambilan air oleh NRucl, NRcl, {CTSAc}NRucl dan {CTSAc}NRcl telah dikaji. Daripada kajian ini, jumlah peratusan air dalam NRcl, NRucl, {CTSAc}NRcl dan {CTSAc}NRucl selepas 48 jam didapati berjumlah 1.8%, 3.0%, 75% dan 131%, masing-masing. Pada bahagian kedua, biokomposit terdiri daripada CTSAc/1-N atau CTSAc/2-N dan terkandung dalam NRucl ({CTSAc/1-N}NRcl) atau dalam NRcl ({CTSAc/2-N}NRucl) disediakan. Semua bahan polimer dicirikan menggunakan kaedah spektroskopi FT-IR, TGA dan VPSEM. This research project consists of two parts. In the first part, we determined the stability of acidified chitosan (CTSAc) gel incorporated with known amounts of either 1-Naphthol (product designated as CTSAc/1-N) or 2-Naphthol (product designated as CTSAc/2-N) in water with different pH values. In acidified water (pH ≤ 4), CTSAc/1-N or CTSAc/2-N swelled tremendously and broke apart easily. In neutral water (pH ≈ 7), CTSAc/1-N and CTSAc/2-N swelled but remained intact even after two weeks. In alkalized water (pH ≥ 9), CTSAc/1-N and CTSAc/2-N hardly swelled even after being soaked for three months. In addition, biocomposites comprised of solely CTSAc encapsulated in uncrosslinked natural rubber ({CTSAc}NRucl) and crosslinked natural rubber ({CTSAc}NRcl) were prepared. From the water uptake study, the percentage amount of water in NRcl, NRucl, {CTSAc}NRcl and {CTSAc}NRucl after 48 h was found to be 1.8%, 3.0%, 75% and 131%, respectively. In the second part, biocomposites comprised of CTSAc/1-N or CTSAc/2-N encapsulated in NRucl ({CTSAc/1-N}NRucl or {CTSAc/2-N}NRucl) and in NRcl ({CTSAc/1-N}NRcl or {CTSAc/2-N}NRcl) were prepared. All polymeric materials were characterized by means of FT-IR spectroscopy, TGA and VPSEM.