封闭聚氨酯纸张增强剂的制备及应用

Preparation and Application of Blocked Polyurethane Paper Strength Agent

摘要:

以咪唑为封闭剂，异佛尔酮二异氰酸酯（IPDI）、聚己内酯二醇、N–甲基二乙醇胺(MDEA)、己二酸二酰肼(ADH)、双酚A、自制N–[（1，1–二甲基–2–乙酰基）乙基]–β–二羟乙氨基丙酰胺（DDP）为原料制备了封闭型阳离子聚氨酯纸张增强剂(CBPU)。用傅里叶变换红外光谱(FT-IR)、动态激光光散射(DLS)和扫描电子显微镜（SEM）对CBPU分子结构、乳液粒径及纸张表面形貌进行了表征，研究了封闭率对乳液粒径的影响。探讨了封闭率及乳液添加量对纸张力学性能的影响。结果表明，产物分子结构中出现了叔胺基、咪唑环和氨基甲酸酯结构。乳液粒径随着封闭率的增加而增大。增加CBPU的封闭率及用量能明显提高纸张的强度指标，尤其是湿强度。当CBPU封闭率及添加量为10%与5%(占绝干浆量)时，纸张湿强度为30.32%。

Abstract:

Cationic imidazole-blocked polyurethane (CBPU) was prepared by the reaction of isophorone diisocyanate (IPDI), Polycaprolactone glycol, methyldiethanolamine (MDEA), ADH, bisphenol A, N-[(1, 1-dimethyl-2-acetyl) ethyl]-β-dihydroxyethylamino propanamide (DDP) and imidazole as blocking agent. Fourier transform infrared spectroscopy (FT-IR), dynamic laser light scattering (DLS) and SEM were used to characterize the structure of CBPU, the particle size and the surface morphology of the paper. Influence of the blocked ratio on the particle size was studied. At the same time, effects of the blocked ratio and the dosage of CBPU on the physical properties of the treated paper were also studied. The experimental results show that structures of tertiary amine group, imidazole ring and urethane group are found in CBPU molecular structure. The particle size is nearly related to the blocked ratio of CBPU. The paper strength, especially the wet strength can be obviously increased with the increasing of the blocked ratio and the dosage of CBPU. The wet strength is 30.32% when the blocked ratio and dosage of CBPU are 10% and 5%.