Which Material is the Best Insulator?

I presented these results on a line graph.

The graph shows the rate the water temperature decreases when insulated by the different materials. The results are very close together but they clearly show that the blue knitted acrylic is a successful insulator. It also shows obviously that the test tube with no insulation decreased fastest. I also shows that the white pleated cotton and the pink woven wools temperature also decreased rapidly.
The table below shows the difference between the start temperature and the end temperature for each material. It also shows the average heat loss per second.

Material Start TemperatureºC End TemperatureºC Average heat loss per second ºC
Carpet material

 By looking at the table it is clear that the water with no insulation decreased in temperature more rapidly than the boiling tubes with material insulation. I expected this. The other materials decrease in temperature in the following order:

Analysing my Results and Observations
My results state clearly that the best insulator material was the Blue Knitted Cotton. This does not match my prediction entirely because I predicted that a light coloured material would be the best insulator. However it does match my prediction because the Blue Knitted Cotton has the most air pockets. This means that the primary factor in preventing heat loss is stopping convection currents and trapping warm air. The reduction of convection currents must have been grater then the radiation to make this material the most efficient insulator.

The two most inefficient insulators were the White pleated cotton and the Pink woven wool. This surprised me because I thought that the white pleated cotton would be an efficient insulator. The White pleated cotton has little air pockets because it is pleated. This method reduces the amount of air pockets in the fabric. The pink woven wool I predicted would be a poor insulator because it is a dark colour. It also has little are pockets as it is woven. Therefore this result matched my prediction.

The Cream woven wool is a fairly good insulator. The fabric is woven so has a restricted amount of air pockets, but is of a light colour so reflected heat back into the boiling tube.
This resulted collaborated with my prediction

Evaluating my results
My results clearly showed how the two factors I predicted effected the materials efficiency. It also showed to what extent the factors affected the efficiency of the insulator. I concluded that the best insulator was the Blues Knitted Acrylic material, and also put the other materials in order of efficiency. I think my results achieved my aim and matched my prediction.

Evaluating the Investigation
The investigation was fair and the experiments I conducted achieved the required results. The experiments were accurate and produced correct answers with no anomalous results. If I conducted the experiment again I would use a wider variety of materials with a wider range of colours. I would want to do this because then I could investigate further into how the colour of the material effects my results. I would use the same material but in different colours for each test. I would also use the same colour material but in different textures e.g. woven pleated, platted, knitted etc. This would enable a more accurate evaluation of results.

The method I chose to use was successful and worked well within the investigation, it was stable and fair. I would not change the method if I repeated the investigation.

Overall I think my investigation was successful as it achieved the required results fairly and accurately.