56 results about "Polyvinyl alcohol foam" patented technology

The invention discloses a halogen-free flame-retardant polyvinyl alcohol foam material and a preparation method of the halogen-free flame-retardant polyvinyl alcohol foam material. The preparation method comprises the steps of preparing composite powder by uniformly mixing 100 parts of polyvinyl alcohol, 20-35 parts of nitrogen-phosphorus halogen-free flame retardant, 0.1-10 parts of catalyst and 0.1-10 parts of nucleating agent, adding the composite powder into mixed solution formed by 0.1-10 parts of surface active agent, 0.1-10 parts of cross-linking agent and 30-40 parts of plasticizing foaming agent, and swelling sufficiently at the temperature of 60 DEG C-80 DEG C, and then continuously extruding and foaming to obtain the halogen-free flame-retardant polyvinyl alcohol foam material at the temperature of 140 DEG C-180 DEG C and with the pressure 8-10MPa. According to the halogen-free flame-retardant polyvinyl alcohol foam material provided by the invention, the limit oxygen index reaches 36%, the vertical burning reaches L94-V0 level and the material can extinguish automatically without fire, the halogen-free flame-retardant property is good, the hole density of the foaming material can be improved, and the halogen-free flame-retardant polyvinyl alcohol foam material can be widely applied to the fields of heat insulation, sound isolation, shock absorption, packaging, sport equipment, clothes and back cushions, soles, sofa, cushions and the like. In addition, the foam is extruded continuously by melting, so that the preparation process is simple, low in cost and environment-friendly, and the halogen-free flame-retardant polyvinyl alcohol foam material is suitable for large-scale industrial production.

The invention relates to a preparation method of a polyvinyl alcohol / silicon dioxide microporous foaming material with cells good in stability and not easy to collapse. The preparation method comprises the three steps: (1) preparing silicon dioxide containing a polar group; (2) preparing a polyvinyl alcohol composition, wherein the polyvinyl alcohol composition contains polyvinyl alcohol, silicondioxide containing the polar group in the step (1) and a plasticizer; and (3) placing the polyvinyl alcohol composition into a high-pressure die, and preparing a polyvinyl alcohol microporous foamingmaterial by using a specific process. The method disclosed by the invention has the following advantages that silicon dioxide containing the polar group is capable of reducing free energy barriers ofcell nucleation and providing heterogeneous nucleation loci for polyvinyl alcohol foaming, so that the cell nucleation rate is increased, cells are not easy to collapse in a foaming process, and the polyvinyl alcohol / silicon dioxide microporous foaming material has better mechanical properties than pure polyvinyl alcohol foam.

The invention provides a polyvinyl alcohol / montmorillonite nano-alloy foam material and a preparation method thereof. The alloy foam material is prepared through using 55-95 parts by weight of polyvinyl alcohol powder, 5-40 parts by weight of a plasticizer, 0.01-5 parts by weight of montmorillonite and 0.25-5 parts by weight of a chemical foaming agent, wherein the consumption of the chemical foaming agent is calculated on the basis of using the dosage of polyvinyl alcohol as 100 parts by weight. Montmorillonite has the effects of a melt reinforcing agent, optimizes the foaming molding process of polyvinyl alcohol, and makes the foam material more suitable for the fusion extrusion foaming processing. Compared with polyvinyl alcohol foam materials without montmorillonite, the alloy foam material has the advantages of uniform cellular dimension, reduced blow hole and combined hole phenomena, and obviously decreased foam density.