[The relationship between FTIR spectra of PVA film and its heat preservation capability].

Polyvinyl alcohol (PVA), polyethylene (PE) and ethylene-vinyl acetate copolymer (EVA) film was prepared. The optic capability, infrared transmittance and heat preservation capability of the films were studied respectively. The result indicated that the haze degree of the PVA film decreased about 15% and 12% than PE film and EVA film; PVA film transmittance of IR was more or less than other films in the 7-14 microm wavelength range so that the temperature of greenhouse could be increased effectively in daylight. It was just 16.2% about 20% less than EVA film, and 50% less than PE film. The PVA film could be used as agricultural film in greenhouse to promote heat preservation performance greatly.

[Preparation of EVOH film and infrared spectroscopic study of its heat preservation property].

EVOH, PE and EVA films were prepared by extrusive blowing techniques, the optic capability, transmittance, haze, infrared anti-transmittance and heat preservation of the films were studied by IR spectroscopy and optic block. The result indicated that the haze degree of the EVOH film decreased about 10% and 5% compared to PE film and EVA film respectively, EVOH film's transmission of IR is much less than other films in the 2.5-25 microm wavelength range, it is just 9.03% in 7-14 microm wavelength range, and about 27% less than EVA film, while much less than PE film. It was found that EVOH film has much better capability of infrared anti-transmittance and point-blank light transmission than other two kinds of films. It was good for calefaction and heat preservation of greenhouse.

[Infrared spectroscopic studies of the effect of hydrotalcite on the capability of agricultural film].

Different kinds of hydrotalcite and their effects on the optic capability, transmittance, infrared anti-transmittance and heat preservation of agriculture film were studied by IR spectroscopy. It was found that the haze degree of the film decreased about 1.5% because the diameter of the hydrotalcite made in Dalian was bigger than those made in Japan. Compared to the french chalk, the hydrotalcite had much better capability of infrared anti-transmittance. But from the spectra of hydrotalcite, whichever made in Dalian or in Japan, there was no infrared absorption in the region of 1100-1200 cm(-1). Compared with the wavelength of 9-11 microm, the absorbance band at 1360 cm(-1) had a little shift. Hence, the capability of heat preservation of hydrotalcite-added agriculture film would be studied in the future work.