Thermoanalytical investigations on paper covers of social wasps

Paper nests of wasps and hornets were investigated by means of differential scanning calorimetry (DSC), thermogravimetry (TG) in combination with mass spectrometry (MS), combustion calorimetry (CC) and some other biophysical techniques. Nests are constructed of thin paper layers (0.1 mm thick, area density 76.5 g m(-2)) formed of rotten wood and strengthened with saliva as adhesive. The nest material is water repellent with extremely low water co ntent (about 3%). Paper nests establish a microclimate for the insect colon y due to the good thermal insulation (heat conductivity 0.08-0.20 W (degree s C m)(-1) comparable to that of some bird nests or of good natural and tec hnical insulators. DSC and TG thermograms show that cellulose is the main c omponent in the wasp paper offering high tensile strength against deformati on and a low specific weight for light construction and easy transport. (C) 2000 Elsevier Science B.V. All rights reserved.