However, in ascidians high concentrations of carbohydrate can be explained by the presence of a protective coat, characteristic of tunicates, composed of tunicin, a substance similar to cellulose (EOL, 2013).
In a parallel interpretation, we hypothesize that the protective coat of tunicin could represent a possible constraint to the full extraction of protein of P.
Nanometric monocrystals of cellulose, commonly referred as whiskers, can be obtained from various sources such as wood (2), tunicin
(3), ramie (4).
Mathew AP, Dufresne A (2002) Morphological investigation of nanocomposites from sorbitol plasticized starch and tunicin
(Although no source of pure I[alpha] has yet been discovered, pure I[beta] is found in the cellulose produced by tunicin
, a marine animal.)
During the reinforcing study of a copolymer matrix from latex phase by tunicin
whisker, it was observed that processing parameters may have effect in the following ascending order of their reinforcement efficiency (tensile modulus and strength): extrusion < hot pressing < evaporation; and this behavior was attributed to the probable breakage and/or orientation of whiskers during processing (52).
Cellulose nanowhiskers, nanocrystals, or nanofibers have been isolated and collected from microcrystalline cellulose (12), (26), cotton (27), tunicin (15), flax (28), hemp (13), ramie (16), wood (29), and sisal (30) fibers as well as from bacterial cellulose (31) using several methods, including physical, chemical, biological, and electro-spinning or a combination of these methods (13), (26), (32), (33).
This kind of phenomena has also been observed from the DMTA results for ramie nanocrystal- or tunicin nanowhiskers-based PS nanocomposite films (16), (45).
Cellulose whiskers with a diameter of few nanometers were separated from wheat straw and tunicin and were used as reinforcements in polymer matrices .
The great advantage of using cellulose microfibrils for polymers reinforcement arises from the remarkable mechanical properties of such fibers: Young's modulus along the chain axis for native cellulose is 167.5 GPa (calculated value) and the modulus of tunicin whiskers is 143 GPa (experimental value) .
Mixtures of this latex and tunicin
whiskers were prepared to produce composites having weight fractions of cellulose ranging from 0% to 12%.
There have been several published studies on the extraction of cellulose nanofibers from different resources, such as wheat straw (Bhatnagar and Sain 2005, Alemdar and Sain 2008), tunicin
(Favier et al.