Chitin from shrimp shells

Catalog	ACM1398614-11
CAS	1398-61-4
Structure
Synonyms	(1,4)-N-acetyl-D-glucos-2-amine
Canonical SMILES	CC(=O)N[C@@H]1[C@H](O)O[C@@H](CO)[C@H](O)[C@H]1O
InChI	1S/C8H15NO6/c1-3(11)9-5-7(13)6(12)4(2-10)15-8(5)14/h4-8,10,12-14H,2H2,1H3,(H,9,11)/t4?,5?,6?,7?,8-/m1/s1
InChI Key	OVRNDRQMDRJTHS-WTZNIHQSSA-N
Form	powder
Grade	practical grade
MDL Number	MFCD00466914
Type	biological source: shrimp (Pandalus borealis)

Case Study

Chitosan Powder as Filler in Natural Rubber Vulcanizates

Egbujuo, Wisdom Okechukwu, et al. International Review of Applied Sciences and Engineering, 2020, 43-51.

The effect of chitosan in different contents on the mechanical properties of NR/chitosan vulcanizates with carbon black as reference filler was studied. It was found that the tensile strength of chitosan-filled natural rubber (NCH) and carbon black-filled natural rubber (NCB) vulcanizates increased with increasing filler content, reaching an optimum at 30 phr and then decreasing. The hardness, impact and abrasion resistance of NCH and NCB vulcanizates increased with increasing filler content. The tensile strength and abrasion resistance of the vulcanizates containing different percentages of carbon black and chitosan (CBCH) blends increased with the addition of more carbon black (CB), while the hardness and impact strength increased with increasing chitosan content.
Preparation of rubber mixes
· Natural rubber was masticated and combined with additives using a two-roll mill, and the vulcanizates were prepared according to the standard procedure outlined in ASTM D 3184-80, adhering to a specific mixing formula. Three different batches of natural rubber (NR)/chitin vulcanizates were created.
· The first batch included NR mixed with chitosan (CH) at filler levels of 10, 20, 30, and 40 phr, designated as NCH 10 to NCH 40.
· The second batch featured NR blended with carbon black (CB) at the same filler levels, labeled NCB 10 to NCB 40.
· The third batch comprised three formulations of NR mixed with varying ratios of carbon black and chitosan fillers, all containing 40 g of filler. The specific compositions were 40% CB/60% CH, 50% CB/50% CH, and 60% CB/40% CH.

Preparation of Biocompatible Chitin Aerogels

Ding, Beibei, et al. Journal of Materials Chemistry, 2012, 22(12), 5801-5809.

Nanoporous aerogels were prepared from chitin using NaOH-urea aqueous solution as solvent and ethanol as coagulant. Then, highly porous and mechanically strong chitin aerogels were prepared by ethanol gelation of the chitin solution followed by supercritical CO2 drying. The obtained chitin aerogels possess low density (0.23-0.27 g cm-3), large surface area (up to 366 m2 g-1), moderate thermal stability and high physical integrity up to 270 °C, significant High mechanical properties and biocompatibility.
Preparation procedure of chitin aerogel
· To enhance chitin solubility, raw chitin powder was subjected to sequential alkaline (1 M NaOH) and oxidative (0.3% NaClO2) treatments, followed by thorough washing. This process was repeated twice. Purified chitin powder was then freeze-dried and stored in a desiccator.
· A desired amount of purified chitin powder was dispersed in a 11:4:85 NaOH-urea-water mixture to form a 3-8 wt% suspension. This suspension was frozen, thawed, and centrifuged to remove air bubbles.
· The resulting chitin solution was spread onto a glass plate, coagulated with ethanol, and washed extensively with deionized water. The hydrogels were subsequently solvent-exchanged with t-butanol or ethanol. Chitin gels containing water or t-butanol were frozen and freeze-dried, while those containing ethanol were dried using supercritical CO2.