The Research Of New Packaging Materials For Photovoltaic Solar Cells

The transparent high performance polyurethane(PU) is supposed to be as encapsulatingmaterial of photovoltaic cell. In this study, the polyester polyols were synthesized by using1,4-cyclohexanedimethanol(1,4-CHDM) and1,6-hexanediol(1,6-HD) with the mixture ofdifferent diacids as1,4-cyclohexanedicarboxylicacid(1,4-CHDA),1,6-adipic acid (1,6-AA).The polyester polyols were charactered by a gel permeation chromatography(GPC), fouriertransform infrared spectroscopy(FTIR) and differential scanning calorimeter(DSC).All the polyester polyols were crosslinked with isophorone diisocyanate(IPDI) andhexamethylene diisocyanate(HDI) trimer to form polyurethane coating films. Seanning andtransmission electron microscopy(SEM) and atomic force microscope(AFM) analyses resultsshowed that PUs of the different sequences soft-paragraph exist micro-phase separation，andthe hard segment was more uniform scattered in soft phase. The crystalline and mechanicalproperties of PUs were changing with the soft phases. The thermal property of PUs werecharacterized by a differential scanning calorimeter(DSC), thermal gravimetric analysis(TGA)and dynamic mechanical thermal analyzer (DMTA).As the“molecular bridge”adhering materials with different properties, silane couplingagents has been applied widely in composite materials, coatings and adhesive agents.Consequently，this dissertation Paid attentionto the following work: selecting three optimalsilanes(KH-550, KH-560, KH-570), studying their processes of hydrolysis and thepreparation of silane films, testing and characterizing the properties and sturcture of the films.The result showed that in order to obtain more silanol, hydrolyzing in mixing solvent withwater and ethnaol(or methanol) had great better effect than only in pure water or ethanol.With hydrolysis time inereasing, the sability of silane solution decreased. The chemicalstructure and property of silane films were characterized and analyzed by a series of detectionmethods which included the attenuated total reflection fourier transform infraredspectroscopy(ATR-FTIR) and Seanning and transmission electron microscopy(SEM). Thesilanol highly crosslinked to polysiloxane with low degree of polymerization. Eeffet of silanefilms on the adhesive strength between PU and metal substrates was investigated. The resultshowed that adhesive strength of silane films gradually increased and then decreased with the curing time and temperature enhancing. The adhesive strength of three kinds of silane filmswith the same concentration: KH-550> KH-560> KH-570.