Preparation And Research On Humidity-controlling Coating In The Hot Summer And Cold Winter Regions

Relative humidity of indoor air has important influence on thehuman body comfort, indoor air quality, the maintenance of furnitureand books. When humidity is low, dry air can easily lead to rough skinwrinkling and cracking, and cause diseases such as atopic dermatitis,skin itching; When the humidity is too high, wet air can cause humanbody moisture to evaporate easily, affect the normal body temperatureregulation, make people feels chest compression, difficulty breathing.This article aims to develop a has better humidity controllingcoatings through the study of damping mechanism, damping coatingformula designs in connection with high relative humidity anddehumidification cycle long climate characteristics in the hot summerand cold winter regions,First,optimizing inorganic mineral material sepiolite andpolyacrylic acid sodium of Super Absorbent Polymer （SAP） as humiditycontrolling materials in coatings. Analyzes the specific surface area andmicrostructure of the sepiolite, and modifys its humidity performancethrough alkalization treatment, acid activation and calcium chlorideactivation. Gains the best solution of modifying humidity performanceof sepiolite.The best solution is: first, using the solubility of3%NaOHto deal with the hybridization of sepiolite, then calcium chloridemodified on sepiolite.When the mass ratio of the sepiolite to calciumidis1:0.5,1:1,1:2,1:4, the moisture absorption rate of modified sepiolitesamples is17.735%,20.253%,36.858%and66.215%, its moistureabsorption rate is2.51,2.86,5.21,9.36times to sample B1.Second, selecting sepiolite as humidity materials, styrene acrylicemulsion as binders, TiO₂as paint, CaCO₃as filler, manufactures ninesamples of inorganic mineral humidity controlling coating throughorthogonalization test design, and tests the humidity controllingperformance of the coating samples. Results show that sample25th has abest humidity controlling performance, maximum moisture absorptionrate is10.137%, the maximum moisture desorption is5.287%. Theformula of sample25th is:350g styrene acrylic emulsion+40gsepiolite+40g TiO₂+40g CaCO₃; Intuitive analysis results of the best formula is: the best formula of intuitive analysis about maximummoisture absorption rate is:250g styrene acrylic emulsion+40gsepiolite+80g TiO₂+60g CaCO₃, the best formula of intuitive analysisabout maximum moisture desorption rate is:350g styrene acrylicemulsion+40g sepiolite+40g TiO₂+60g CaCO₃.Finally, selecting Super Absorbent Polymer and sepiolite ashumidity materials, styrene styrene acrylic emulsion as binders, TiO₂aspaint, CaCO₃as filler, manufactures sixteen samples of compoundhumidity controlling coating through orthogonalization test design, andtests its humidity controlling performance and basic decorativeperformance of the coating samples. Results show that sample4th has abest humidity controlling performance among sixteen samples,maximum moisture absorption rate is14.941%, the maximum moisturedesorption is12.222%. The best formula of intuitive analysis is the sameas the formula of sample4th.The formula of sample4th is:120g styreneacrylicemulsion+2gSAP+40g sepiolit+20gTiO₂+20gCaCO₃.The basicdecorative performance of sixteen coating samples reach Standardbasically.Humidity controlling performance and formula composition ofsample25th and4th has guiding significance in improving the indoorhumidity environment and researching Humidity controlling coatings.