PENGARUH PENAMBAHAN CLAY DAN GLISEROL TERHADAP STRUKTUR MIKRO DAN UJI TARIK FILM KOMPOSIT CHITOSAN/CLAY/GLISEROL SEBAGAI MATERIAL PENGEMAS MAKANAN YANG RAMAH LINGKUNGAN
EARTHA SENTRA SUMAKNA ASIANTO, Dr. Kusmono, ST., MT.
2017 | Skripsi | S1 TEKNIK MESINUntuk saat ini, bahan untuk pengemas makanan banyak menggunakan bahan plastik sintetis seperti polietilen, polisterin, dan lain-lainnya. Namun pada kenyataannya plastik sintetis tersebut menimbulkan masalah lingkungan akibat sulit terurainya plastik sintetis oleh mikroorganisme. Chitosan merupakan salah satu jenis biopolimer yang memiliki sifat biodegradable, bioactive, dan biocompatible sehingga dapat digunakan sebagai material pengemas makanan yang ramah lingkungan. Studi komposit chitosan untuk aplikasi pengemas makanan yang ramah lingkungan akan dilakukan pada penelitian ini. Pengaruh penambahan clay dan gliserol untuk memberikan sifat plastis terhadap sifat tarik komposit chitosan dipelajari pada penelitian ini. Film komposit chitosan/clay diawali dengan pembuatan larutan chitosan/clay. Sebanyak 2 gram chitosan dilarutkan ke dalam 100 ml larutan asam asetat 1 persen, larutan tersebut diaduk dengan magnetic stirrer pada suhu 90 derajat C selama 60 menit dan selanjutnya divakum selama 15 menit. Suspensi chitosan/clay disiapkan dengan cara clay dilarutkan ke dalam 100 ml asam asetat 1 persen dan diaduk pada suhu kamar selama 120 menit. Kandungan clay divariasi dari 0,1,3,5,7,10, dan 15 persen berat. Kedua larutan dicampur dan diaduk selama 2 jam. Larutan tersebut dituangkan ke dalam cetakan akrilik untuk membuat spesimen uji tarik. Film komposit chitosan/gliserol disiapkan dengan cara mencampurkan gliserol dengan variasi 20,25, dan 30 persen berat ke dalam larutan asam asetat 1 persen dan chitosan. Larutan tersebut diaduk selama 1 jam pada suhu 90 derajat C. Pengaruh penambahan clay dan gliserol terhadap sifat tarik dipelajari melalui uji tarik, kandungan struktur mikro chitosan dipelajari mrnggunakan X-Ray Diffraction (XRD) dan ikatan kimia antara chitosan/clay/gliserol dikarakterisasi dengan Fourier Transform Infra Red (FTIR). Penambahan clay sampai 10 persen berat meningkatkan kekuatan tarik, tetapi penambahan 15 persen berat clay menurunkan kekuatan tarik. Regangan komposit chitosan/clay meningkat seiring dengan kenaikan clay. Penambahan 20 persen gliserol meningkatkan kekuatan tarik dan regangan. Modulus elastisitas chitosan turun drastis dengan penambahan gliserol . kekuatan tarik tertinggi dicapai dengan penambahan 5 persen clay dan 20 persen gliserol ke dalam chitosan.
Nowadays, food packaging often uses synthetic plastic material such as polyethylene, and polystyrene. Unfortunately, synthetic plastics may pose environmental concerns due to its long time for decomposition. Chitosan, a material studied in this research, is a biopolymer with biodegradable, bioactive and biocompatible properties which may be used as food packaging material. The aim of this research is to study the advisability of using chitosan composite for environmentally friendly food packaging applications. The effect of clay and glycerol composition to chitosan's tensile and plastic properties were studied in this research. In this study, 2 g of chitosan was first dissolved in 100 ml of a 1% solution of acetic acid. The solution was then stirred with a magnetic stirrer at a temperature of 90 degree C for 60 minutes. The solution was then vacuumed for 15 minutes. The chitosan / clay suspension was prepared by dissolving the clay in 100 ml of 1 percent acetic acid and stirred at room temperature for 120 minutes. The content of clay was varied from 0,1,3,5,7,10, and 15 percent by weight. The two solutions were mixed and stirred for 2 hours. The solution was poured into an acrylic mold to create specimens for further tensile tests. Chitosan-glycerol composite films are prepared by mixing glycerol with a variation of 20.25, and 30 percent by weight to a 1 percent acetic acid solution and chitosan. The solution was stirred for 1 hour at a temperature of 90 degree C. The effect of clay and glycerol composition on the tensile properties are studied by tensile testing. Microstructure observations of the chitosan were studied using X-Ray Diffraction (XRD) and chemical bonding between chitosan / clay / glycerol were characterized by Fourier Transform Infra Red (FTIR). Addition of clay up to 10 percent by weight increases the tensile strength, but the addition of 15 percent lowers the tensile strength. Strain composite chitosan / clay increases with the increase in clay. The addition of 20 percent glycerol increases the tensile strength and elongation. The elastic modulus of chitosan dropped significantly with the addition of glycerol. The highest tensile strength was achieved during the addition of 5 percent clay and 20 percent glycerol into chitosan.
Kata Kunci : chitosan, clay, film komposit, sifat mekanis
