Preparation Of Biodegradable Poly(Butylene Succinate) Foam

Plastic foam is a new materials, which is of plastic as a substrate and contains a lot of bubbles. It can be viewed as composite plastic whose filler is gas. Plastic foam has common characteristics such as light weight, low thermal conductivity, good thermal-proof properties, well impact load absorbing ability, excellent buffer insulation properties, and high specific strength. So it has been widely used in packaging, construction and other fields. However, it is difficult to degrade and recycle the traditional foam. So with the increase of the production, the harm to the environment is also growing. The growing plastic pollution is perceived as the threat to the ecosystem, particularly in large cities which has high cost of land. Incineration is on the high demand for facility, which requires a lot of capital investment and brings some environmental problems, so that developing degradable plastics becomes a research hot spot recently.It’s easier to control the degradation conditions and time of the biodegradable polymer which is a kind of degradable plastic and more environmental friendly, so biodegradable plastic becomes an important branch of the development of the degradable plastic. Poly(butylene succinate) (PBS), as a kind of the biodegradable polymer, whose performance is similar to that of the common plastic, has high processing performance and takes the place of many common plastic products to be researched at this stage.In this thesis, PBS plastic foam was molded from PBS resin, ammonium bicarbonate as the foaming agent. The foam with relatively smaller bulk density was made by a series of experiments when the foaming agent content is 5wt%, the processing temperature of 130℃, processing pressure of 10MPa, holding time of 5min. The foaming quality and the bending strength of the product can be improved by adding nucleating agent. The bulk density of the product reaches minimum when the nucleating agent content is 3wt%. Adding plasticizers has little effect on the bulk density of the product. To solve the problem of the low bending strength of the PBS and the large brittle of the product, the effect of material ratio and different process parameters on product bulk density and bending strength were studied by using toughening PBS as raw materials. The foam with smaller bulk density can be made when the foaming agent content is 5wt%, and the process parameters are: the processing temperature of 140℃, processing pressure of 10MPa, packing time of 7min. Compared with the PBS foam, the toughening PBS foam does not have too much difference in the bulk density, but improves greatly the bending strength of the product. In addition, it was shown that the bending strength of the product has little effect on the change of the process parameters.