Preparation Of Na-Alginate Essay

2.2 Production of Alginate Wool:

In all the following experiments the chlorhexidine digluconate was used as 20% (w/v) aqueous solution. Alginate was dissolved at 1% (w/v) in demineralized water. Then the solutions were mixed under constant magnetic stirring at room temperature, and were left to stand to allow the entrapped air bubbles to be removed, then poured on petri dishes.

2.2.1 Preparation of Na-Alginate 1% solution and Na-alginate wool:

At the beginning, Na-Alginate 1% solution should be prepared. 1g of Na-Alginate was weighed. In a flask 100 ml of demineralized water was placed and stirred with magnetic stirrer. Then Na-Alginate was added in portions to the water with constant stirring, the preparation lasts for 4 hours.

Then different

2.2.2.3 Copper-Alginate:

50 ml of copper chloride was added to 50 ml sodium alginate 1% solution and stirred. blue gel formed directly (pH=3.45). Because of its blue color, no further experiment was carried out.

2.2.2.4 Calcium Alginate:

Molecular Formula: (C12H14CaO12) n

Alginic acid mixed with half amount of calcium carbonate. After 10 Minutes a white wool developed, and it is insoluble in water. The problem here was the production of Co2 gas and formation of bubbles. The produced wools were brittle and

2.2.2.5 Mg-Alginate:

50 ml of magnesium chloride was added to 50 ml sodium alginate 1% solution and stirred. after adding acetone, fibrous filaments were produced (pH=5.71). Mg-Alginate was one of the best produced wool and had very good qualities.

2.2.2.6 Zn-Alginate:

100 ml of zinc chloride was added to 100 ml sodium alginate 1% solution and stirred. clear colorless thick gel was produced (pH=5). Then it was tried to increase pH by adding NaOH. Nevertheless, it maintains its form and remains clear gel

2.2.2.7

When pH (-- removed HTML --) 5 a solid fibrous wool is produced.

2.2.4 Drying the different alginate wools:

The drying attempts were performed in 3 different methods.

2.2.4.1 Drying with hair dryer: by cold air

It is simple and affordable method, but the quality of the dried wool was not good and the wool wasn't 100% dried.

The different woos become after several minutes of drying brittle and fragile. They had been dried for 20-30 Minutes (80%). Then they were left several days to dry naturally. 2.2.4.2 Drying with drying oven:

Drying was carried out in the laboratory for 24 hours at 30 °C. The product was dried in plastic dishes. The wool becomes a hard and dry, and was easy breakable and difficult to handle with.

2.2.4.3 Drying with freeze