软质PVC中增塑剂在不同溶媒中的迁移行为

研究软质PVC交联前后,增塑剂对苯二甲酸二辛酯在蒸馏水、3%乙酸、10%乙醇和橄榄油浸泡溶媒中的迁移行为。结果表明:增塑剂在蒸馏水和乙醇浸泡溶媒中,前24 h缓慢上升后趋于平缓;在乙酸浸泡环境中,交联改性延迟了增塑剂迁移出来的时间;在橄榄油浸泡溶媒中,前24 h迅速上升后也逐渐趋于平缓,交联改性对增塑剂迁移有一定的抑制作用,凝胶含量越大,迁移率越小。无论PVC交联与否,增塑剂在不同溶媒中的迁移率大小顺序均为:橄榄油>10%乙醇>蒸馏水>3%乙酸。     

Nano-SiO_2对软质PVC中DINCH增塑剂迁移行为的抑制作用

将nano-SiO2引入环己烷-1,2-二甲酸二异壬酯(DINCH)增塑的软质聚氯乙烯(PVC)中,研究了nano-SiO2用量对PVC试片中的DINCH在30℃、95%乙醇浸泡环境中的迁移行为及试片拉伸性能的影响。结果表明:增塑剂的迁移率随着浸泡时间的延长而呈总体上升趋势,前期上升较快,中期缓慢,后期逐渐趋于平衡;nano-SiO2的添加可以降低DINCH的迁移率,并且当nano-SiO2用量为1份时,DINCH在溶剂中的迁移抑制率最大,而此时DINCH的挥发损失率亦最小;另外,随着nano-SiO2用量的增加,PVC试片的拉伸强度和断裂伸长率有所下降,但降幅不大。     

交联软质PVC的制备及表征

以双叔丁基过氧化异丙基苯(BIPB)为交联剂、三烯丙基异三聚氰酸酯(TAIC)为交联助剂制备了交联软质聚氯乙烯(PVC),并研究其不同用量及工艺条件对交联PVC凝胶含量的影响.结果表明:当BIPB用量为1份,TAIC用量为4份,在178℃下交联反应11 min时,PVC凝胶含量可以达到48.9%.     

双马来酰胺酸交联PVC的交联行为研究(Ⅰ)

用哈克流变仪来研究以双马来酰胺酸作为交联剂、DCP(过氧化二异丙苯)为引发剂、DOP(邻苯二甲酸二辛酯)为增塑剂的交联PVC的交联特性。研究表明:PVC交联反应速率随增塑剂用量的增加而减慢,PVC的凝胶率也变低;交联剂用量越多,凝胶率越大;提高反应温度或增加反应时间可提高凝胶率。     

TBC复配增塑对聚氯乙烯防水卷材性能影响的研究

探讨了邻苯二甲酸二辛酯(DOP)和柠檬酸三丁酯(TBC)两种增塑剂对聚氯乙烯(PVC)防水卷材拉伸性能、撕裂性能、尺寸稳定性及增塑剂迁移率的影响。结果表明:在同等增塑剂用量的情况下,TBC增塑体系的力学性能优于DOP增塑体系,但尺寸稳定性和增塑剂迁移率较差。随着TBC/DOP复配体系中TBC含量的增加,PVC防水卷材的断裂伸长率、撕裂强度和尺寸稳定性均呈先增大后减小的趋势,而拉伸强度呈先增大后减小再增大的趋势,增塑剂迁移率呈增大趋势。当TBC/DOP以1:3复配时,PVC防水卷材的拉伸性能、撕裂性能、尺寸稳定性及增塑剂迁移率总体比较理想,均能满足GB/T 12592—2011的要求。     

聚氯乙烯材料中增塑剂迁移率测试方法及影响因素研究

根据增塑剂的迁移特性,确定出一种增塑剂迁移率的测试方法。结果显示,测试方法的最适合测试条件为,时间2 h,温度60℃,增塑剂添加量60份,试片厚度1 mm。根据试验数据,有利于PVC制品生产厂对储存温度、时间、压力(制品叠加所产生)的选择,来最大程度降低制品中增塑剂的迁移风险。同时研究了加工温度、PVC树脂粉规格牌号、增塑剂种类、稳定剂添加量对增塑剂迁移的影响程度。并对各试验现象,从内部分子结构及形态,给出迁移机理的解释,为将来了解新助剂的迁移特性提供理论基础。     

PVC中增塑剂迁移和抽出问题

讨论了聚氯乙烯（PVC）中增塑剂抽出和迁移的危害性和基本原理,重点介绍了影响增塑剂抽出和迁移的主要因素,如：增塑剂相对分子质量和分子结构、环境温度、增塑剂含量、介质和时间。归纳总结了各种能有效抑制PVC中增塑剂抽出及迁移问题的解决办法及研究成果,主要为添加聚酯增塑剂、添加纳米粒子、使用离子液体、表面改性、表面交联、表面喷涂防护涂层等。     

PVC食品包装膜中增塑剂DEHA的迁移行为

研究了PVC食品包装膜中的增塑剂DEHA在模拟油(正己烷)中的迁移行为,测定了影响迁移过程的速度常数和活化能,并探讨了它们与温度和DEHA初始浓度的关系。实验结果表明:速度常数随浸泡温度的上升和PVC膜中DEHA的起始浓度的提高而增加。     

助剂对聚氯乙烯辐照改性的影响

本文研究了代表性的增塑剂邻苯二甲酸二丁酯(DBP)、稳定剂硬脂酸铅及多官能团单体三羟甲基丙烷三丙烯酸酯(TMPTA)和季戊四醇四丙烯酸酯(PETA)对聚氯乙烯(PVC)γ辐照改性的影响,测试了不同配方的 PVC 于不同剂量辐照时的凝胶含量、力学性能、热失重性能。结果表明,DBP 和硬脂酸铅对 PVC 的辐照交联是有益的。多官能团单体 TMPTA 和 PETA 对 PVC 的辐射交联有很大的促进作用。加入多官能团单体的 PVC 经辐照后,其拉伸强度、耐热性能和增塑剂束缚性能大大改善。     

光对聚氯乙烯的作用

为了研究硬质及软质聚氯乙烯薄片中聚氯乙烯树脂(PVC)由于光的作用而分解的历程,制备了几种添加热、光稳定剂的(PVC)薄片,进行大气曝露和耐候试验箱人工老化的比较试验。考察样品被光照射后的PVC凝胶生成量、平均聚合度和分子量分布曲线的变化,确定了PVC分子中有多少发生降解和交联。在大气曝露试验中增塑剂的存在使PVC的耐光性获得良好结果。但在耐候试验箱的试验中,有无增塑剂并不产生明显的影响。此外,在不含增塑剂的薄片的人工老化试验中,含硬脂酸铅的结果是良好的,故不能忽视由于加工及光照射装置内温度上升而引起的热分解。     

不同度数白酒介质中PVC制品增塑剂迁移行为研究

采用高效液相色谱仪测定聚氯乙烯（PVC）制品中传统增塑剂邻苯二甲酸二辛脂（DOP）、对苯二甲酸二辛脂（DOTP）和环保增塑剂柠檬酸三丁酯（TBC）、乙酰柠檬酸三丁酯（ATBC）,在42 °、46 °、55 °白酒中的迁移规律,并用Gaussian 03程序对其结构进行模拟计算,探讨了分子结构影响增塑剂迁移行为的机理。结果表明,随着与介质接触时间的延长、白酒度数的增大,增塑剂的迁移率逐渐增大;不同种类分子结构的增塑剂的迁移能力有较大的差异性,增塑剂分子的偶极矩越大,其分子极性越强,增塑剂与PVC相容性就越好,其迁移率越小;几种增塑剂中,迁移率大小为：TBC＞ATBC＞DOP＞DOTP。     

Preparation and evaluation of acetylated mixture of citrate ester plasticizers for poly(vinyl chloride)

Tributyl citrate (TBC) and acetyl tributyl citrate (ATBC), as phthalate alternative plasticizers, show limited application due to low migration resistance, high volatilization rate and intense respiratory irritation. Meanwhile, the developed pure citrates, such as butyryl trihexyl citrate (BTHC) due to its high cost, and triisooctyl citrate (TOC) and acetyl triisooctyl citrate (ATOC) due to their low absorption property, are not attractive plasticizers to manufacture phthalate-free poly(vinyl chloride)s (PVCs). In this study, we developed an effective method to synthesize acetylated mixture of citrate esters (ATMC) composed of acetyl (dibutyl-monoisooctyl) citrate, acetyl (monobutyl-diisooctyl) citrate, and a small amount of ATBC and ATOC, as an alternative for phthalate plasticizers. ATMC combines the advantages of ATBC in being easily absorbed and ATOC in having good migration resistance. Characterization results showed that the dynamic viscosity, absorption property and plasticizing efficiency of ATMC11 (1:1 molar ratio of n-butyl alcohol to 2-ethylhexanol) were similar to those of di(2-ethylhexyl) phthalate (DEHP). The thermal volatilization and migration of ATMC11 were less than those of ATBC, and were comparable to those of DEHP, which could be attributed to the improved compatibility with PVC. The performance of ATMC11 was improved compared with that of the mixture of ATBC and ATOC. As an environmental bio-based plasticizer, ATMC11 was demonstrated as a biologically safe plasticizer by biological safety evaluation tests. Therefore, ATMC11 with excellent comprehensive performances and low cost can be candidate as an ideal phthalate alternative for soft PVC formulations.     

Revisiting analysis of phthalate plasticizers concentration in poly(vinyl chloride)

The method of the efficient analysis of di(2‐diethylhexyl) phthalate, tri(2‐ethylhexyl) trimellitate, di(2‐ethylhexyl) terephthalate, and other phthalate plasticizers concentrations in plasticized poly(vinyl chloride) (PVC) was developed. The method is based on quantitative dissolution of the PVC sample in methyl ethyl ketone with the consequent precipitation of PVC with hexane and concentration of phthalate in an organic layer. A capillary column‐based gas chromatographic technique for phthalates separation and quantification was developed and used in conjunction with the PVC and phthalates dissolution technique. The developed method of phthalate plasticizers analysis proved to be relatively fast, reproducible, and straightforward. J. VINYL ADDIT. TECHNOL., 21:197–204, 2015. © 2014 Society of Plastics Engineers     

Recycling of Waste PET: Usage as Secondary Plasticizer for PVC

Postconsumer water bottle poly(ethylene terephthalate) (PET) flakes were depolymerized with ethylene glycol (EG) by the glycolysis reaction in the presence of zinc acetate as the catalyst. In the depolymerization reactions, different weight ratios of PET/EG were used. In order to obtain polyesters used as PVC plasticizers, these glycolysis products containing hydroxyl end groups were reacted with an adipic acid (AA)–containing diacid group at equivalent amounts. In order to obtain PVC plastisols, PVC was dispersed into a plasticizers' mixture composed of di-isooctyl phthalate (DOP) and polyester products by using a high-speed mixer (PVC/plasticizers, 65/35 w/w). For the preparation of plasticizer mixture polyester products were used at a weight ratio of 20%, 40%, 60% of DOP. Plasticized PVC sheets were prepared from plastisols and their glass transition temperatures (T_g), migration, and mechanical properties were determined. The results show that the polyester products obtained from glycolysis products of waste PET can be used as secondary plasticizers, with DOP for PVC.     

Application of new oligomeric plasticizers based on waste poly(ethylene terephthalate) for poly(vinyl chloride) compositions

In this study, chemical recycling products of waste poly(ethylene terephthalate) with oligoesters were used as new plasticizers for poly(vinyl chloride) (PVC). The preparation conditions of the dry blend mixtures of the suspension PVC containing synthesised plasticizers were similar to the conditions of the preparing mixtures with commercial plasticizers. The plasticization efficiency of PVC plasticizers was then examined by analysis of the mechanical, physical and chemical properties, as well as the thermal resistance and migration of plasticizer molecules from polymer matrix. Test results proved that compositions with synthesised oligomeric plasticizers possessed similar or better properties than those containing commercial oligomeric plasticizers and much better properties than those having monomeric plasticizers. Thermal stabilities of the proposed plasticizers were higher than those of the commercial plasticizers either monomeric (bis(2-ethylhexyl)phthalate) or oligomeric, despite the fact that the synthesised oligoesters did not contain any antioxidant. The best properties, especially low volatility, very good mechanical properties, low migration were resulted of the transesterification of the waste PET with oligoesters based on adipic acid, triethylene glycol and 2-ethylhexanol which were selected as plasticizers synthesised on the technical scale. The tested plasticized PVC compositions possessed very good tear resistance, tensile strength, decrease of weight loss after 168 h at 80 °C and low migration. Processing properties of PVC compositions containing these synthesised plasticizers confirmed their effectiveness in these compositions for extrusion process.     

硅烷交联聚氯乙烯的研究

研究了硅烷的种类,增塑剂,交联时间等因素对PVC交联的影响,结果表明,通过调节硅烷的用量可以制备不同交联度的PVC,交联后的PVC其力学性能,尺寸稳定性,体积电阻率,热主为形温度得到提高。     

聚氯乙烯环保型增塑剂的合成及应用

聚氯乙烯中常用的环保型增塑剂主要有柠檬酸酯类增塑剂、对苯二甲酸酯类增塑剂、聚酯类增塑剂、偏苯三酸酯增塑剂、环己烷二羧酸酯类增塑剂、植物油基增塑剂等,通过了解和分析这些增塑剂的特征和合成,推进环保型增塑剂在塑料生产中的应用。     

Synthesis and characterization of biobased polyester PVC plasticizers to industrial manufacturing of tubes

The search for the substitution of phthalate derivatives in the process of polyvinyl chloride (PVC) plasticization is a matter of intensive research, due to the increasing proofs about phthalate toxicity. With this objective, a series of novel saturated polyesters (SPs) were synthesized by polycondensation from different biobased acids and diols, and end-capped with 2-tetradecyloctadecan-1-ol (TDOD). After characterization, the SPs were incorporated in an industrial formulation for flexible PVC and the mechanical properties of the films analyzed by tensile tests, DMTA, and DSC. The tensile tests revealed a similar ultimate tensile strength and a higher elongation at break for the PVC with SP as plasticizers compared with DEHTP (di[2-ethylhexyl] terephthalate). The SP showing the most promising results was chosen to carry on an industrial manufacturing of a transparent tube. The migration tests of the tube show a much less leaching properties compared with tube prepared using the plasticizer DEHTP. All the results indicate that SPs can be an industrially viable and excellent alternative to DEHTP.     

采用凝胶渗透色谱法分析医用PVC中增塑剂的种类及含量

在不对样品进行萃取分离等前处理的条件下,利用凝胶渗透色谱(GPC)示差(RI)-紫外(UV)双检测器连用测定医用PVC粒料中增塑剂的种类及含量.通过RI检测器可以确定粒料中PVC树脂、增塑剂环己烷1,2-二甲酸二异壬酯(DINCH)和环氧大豆油(ESO)的质量分数约分别为70.1%,22.6%和7.3%;通过UV检测器...