【作者】 岳喜贵；

【导师】 姜振华；

【作者基本信息】 吉林大学 ， 高分子化学与物理， 2008， 博士

【摘要】 本论文是以制备全芳香性可交联聚芳醚酮为背景,合成了多种双酚单体,并且在假高稀条件下,用两步法合成了含有羟基的环状单体,通过与双氟单体的反应,最终得到聚芳醚酮的共聚物。通过分子设计,将环状结构引入了聚芳醚酮的主链,侧链和封端。在加入氟化铯的条件下,实现了可溶性聚芳醚酮的热交联反应,并且对交联机理进行了研究。在高温下,氟离子进攻醚键,导致了醚键断裂;生成了酚氧铯盐的结构,氟与另外一端相连;生成的氧铯盐进攻另外的一个环状结构,导致其断裂,并与其联结,因而发生了交联反应。通过流变的测试,得到了环状结构开环的最低温度。与传统的不饱和烃类的交联不同,应用这样的交联方法,在交联聚合物的最终结构中,没有残留脂肪族化合物,并且交联反应为熵驱动的反应,因而没有热量的放出,使高温下的交联反应更容易控制。交联后,聚合物拥有较高的凝胶含量,但是聚合物玻璃化转变温度升高不大,这是由于环状单体交联后分子链之间的距离比较大,因而分子链运动相对容易。因而,相对于不饱和烃交联反应,在相同凝胶含量的前提下,环结构的交联得到的材料韧性更好,有相对较高的断裂伸长率。更多还原

【Abstract】 In recent years there is a considerable interest in the aromatic polymer poly(aryl ether ketone)s among thermoplastic polymers because of their unique combination of toughness, stiffness, thermooxidative stability, electrical performance, flame retardancy and retention of physical properties at high temperatures. So far they have been successfully applied to many fields such as aviation, spaceflight, nuclear energy, communication, telecom, petroleum, machine manufacturing and traffic. However, with the booming development of new science and technology revolution in world, materials with high performance and functionality have been required extensively and urgently. In order to improve the characterization of poly(aryl ether keonte)s further, it is made them to take place crosslinking reaction. Before they are cured processed thermoplastic materials, which can be molded or casted,and then become thermoset through crosslinking reaction, so they have both kinds of advantage of materials. They’re required to introduce crosslinking groups.The dissertation include three parts: crosslinkable fully aromatic poly(aryl ether ketone)s bearing macrocycle of aryl ether ketone; synthesis and crosslinking of poly(arel ether ketone)s bearing macrocycle pendants; synthesis and curing behaviors of aromatic poly(ether ether ktone)s with macrocycle pendent.A novel bisphenol monomer, (3-methoxy)phenylhydroquinone, was synthesized via a three-step synthetic procedure. The cyclization of the bisphenol monomer and 4,4-difluorobenzophenone was carried out under pseudo high dilution condition. Two types of fully aromatic poly(aryl ether ketone)s were prepared by copolymerization of macrocycle of aryl ether ketone (MACEK) containing hydroxyphenyl, 4,4-(hexafluoroisopropylidene) diphenol (HFBPA), and 4,4-difluorobenzophenone. The copolymers have high molecular mass, good solubility and high glass transition temperatures. The copolymers are crosslinkable in the presence of basic initiator and the glass transition temperatures of the copolymers increased greatly after the curing. These cured copolymers exhibit excellent thermal stability, and the 5% weight loss temperatures are around 500 oC in nitrogen.A novel bisphenol monomer, (2,5-methoxy)phenylhydroquinone, was synthesized via a three-step synthetic procedure. The cyclization of the bisphenol monomer and a di-fluoro monomer was carried out under pseudo high dilution condition. Two types of fully aromatic poly(ether ketone)s with macrocycle (MCPAEK) were successfully prepared by copolymerization of macrocycle of aryl ether ketone containing hydroxyphenyl groups, (hexafluoroisopropylidene)diphenol (HFBPA), and 4,4-difluorobenzophenone. The copolymers had high molecular mass, good solubility and high glass transition temperatures. The MCPAEKs exhibited excellent thermal stability due to their wholly aromatic structures. In the presence of CsF, the crosslinking reaction of MCPAEKs could afford fully aromatic thermoset poly(aryl ether ketone)s by ring-opening reaction driven by entropy. After crosslinking, the glass transition temperatures increased greatly. These cured copolymers presented an excellent thermal stability, and the temperatures at the 5% weight loss were above 510 oC in nitrogen. The cured copolymers even possessed good tensile properties and the elongations at break were up to 20%.Novel fully aromatic macrocycle-terminated poly(aryl ether ketone)s (MCPAEK) were prepared by condensation of macrocyclic aryl ether ketone dimers containing hydroxyphenyl groups and fluorine end-capped poly(aryl ether ketone)s oligomers. The MCPAEKs exhibited highly thermal stability due to their wholly aromatic structures. Compared to liner poly(aryl ether ketone)s, MCPAEKs showed much lower melt viscosities at low temperature. In the presence of cesium fluoride (CsF), the crosslinking reaction of MCPAEKs could afford fully aromatic thermoset poly(aryl ether ketone)s by ring-opening reaction. After crosslinking, the glass transition temperatures and complex melt viscosities of the polymers both increased greatly. Though there were some residual CsF or phenoxides produced by ring-opening reaction, the obtained thermoset poly(aryl ether ketone)s had good thermal stability with 5% -Td above 475 oC.更多还原