VAc-VeoVa10乳胶粉对改性水泥砂浆力学性能的影响

针对目前膨胀聚苯板(EPS)外墙外保温系统用水泥砂浆粘结性差、柔韧性差等问题,用醋酸乙烯酯(VAc)与叔碳酸乙烯酯(VeoVa10)共聚乳胶粉对其进行改性。研究了乳胶粉用量对改性水泥砂浆力学性能的影响。结果表明,随着乳胶粉用量的增加,砂浆的粘结强度增加、抗折强度提高、抗压强度降低、柔韧性提高。通过正交试验研究了灰砂质量比、乳胶粉用量、保水剂用量等因素对改性水泥砂浆与EPS以及与基础砂浆粘结强度、抗折强度、抗压强度以及压折比的影响,得出改性水泥砂浆的最优配比为:水泥与石英砂的质量比1:1,乳胶粉质量分数4%,保水剂质量分数0.2%。

The Effect of VAc-VeoVa10 Latex Powder on Mechanical Properties of Modified Mortar

According to the bad caking property and flexibility of cement mortar used in external thermal insulation system,VAc-VeoVa10 latex powder was used to modify the cement mortar.The effect of dosage of VAc-VeoVa10 latex powder on mechanical properties of modified mortar was studied.The results show that with the increase of dosage of latex powder,both the bond strength between modified mortar and expanded polystyrene boards(EPS),and the strength between modified mortar and cement mortar block increased;the flexural strength and flexibility were improved,but the compressive strength decreased.At the same time,the influence of cement/sand ratio,dosage of VAc-VeoVa10 and dosage of water retaining agent on mortar performance was analyzed by orthogonal test,including the bond strength between modified mortar and expanded polystyrene boards(EPS),the strength between modified mortar and cement mortar block by compressive strength,flexural strength,and ratio of compressive strength to flexural strength.By comprehensive consideration,at the cement/sand ratio 1:1,the mass fraction of polymer powder 4%,and the mass fraction of water retaining agent 0.2%,the properties of modified mortar was the best.