Polymers from 12-hydroxymethyltetrahydroabietic acid and its vinyl and acrylate esters

12-Hydroxymethyltetrahydroabietic acid has been homopolymerized by melt condensation and homopolyester has been obtained. Vinyl 12-hydroxymethyltetrahydroabietate has been prepared from 12-hydroxymethyltetrahydroabietic acid by vinyl interchange procedure with vinyl acetate, and has been homopolymerized, copolymerized with vinyl chloride, vinyl acetate, and terpolymerized with styrene and acrylonitrile. The acrylate ester of 12-hydroxymethyltetrahydroabietic acid also has been prepared from 12-hydroxymethyltetrahydroabietic acid and acrylyl chloride. The acrylate thus obtained has been homopolymerized and copolymerized with vinyl chloride and vinyl acetate. Polymers thus obtained have been characterized.     

Polymers containing 12-hydroxymethyltetrahydroabietanol

12-Hydroxymethyltetrahydroabietanol has been polymerized with hexamethylene diisocyanate and a low molecular weight polyurethane produced. Low molecular weight polyurethanes have also been prepared from 12-hydroxymethyltetrahydroabietyl chloroformate, hexamethylenediamine, and sym.-dimethylethylenediamine. 12-Hydroxymethyltetrahydroabietanol has been “end-capped” with tolylene-2,4-diisocyanate and hexamethylene diisocyanate. The resulting diisocyanates have been polymerized with polytetramethylene glycol, hexamethylenediamine and hydrazine.     

Polyesters of phosphoric acid: Synthesis and kinetics of hydrolysis

Three major methods have been elaborated in our laboratory for preparation of polymers with poly(alkylene phosphates) backbones: ring-opening polymerization, poly-condensation and transesterification, and polyaddition. The second method is based on the reaction of the commercially available compounds, namely dialkyl (or diaryl)-H-phosphonates and glycols. Reaction of the aliphatic H-phosphonates with aliphatic glycols is a reversible process, whereas polycondensation of diphenyl H-phosphonates with aliphatic and cycloaliphatic diols is practically irreversible. This latter method has recently been developed and is described in this paper. Poly H-phosphonates with M̄_n up to 40–10³ were prepared. Polymers are easily oxidized and quantitatively converted into the relatively stable poly(alkylene phosphates). Some physical properties of these polymers and kinetics of their hydrolysis is discussed.     

超支化聚酯微光学光致抗蚀剂

超支化聚酯微光学光致抗蚀剂;超支化聚合物;光致抗蚀剂;微透镜阵列     

Polyesters derived from 1,4-oxathian-2-ones

1,4-Oxathian-2-one ( 1a ) was prepared in high yield by oligomerization of methyl(2-hydroxyethyl)mercaptoacetate ( 3 ) followed by catalytic depolymerization in vacuo. A similar sequence starting with methyl(2-hydroxyethyl)sulfonylacetate ( 5 ) afforded the corresponding sulfone, 1,4-oxathian-2-one-4,4-dioxide ( 1c ), however, 1,4-oxathian-2-one-4-oxide ( 1b ) could not be obtained by this procedure. Ring opening melt polymerization of 1a and 1c afforded low molecular weight crystalline polyesters 2a and 2c . Oxidation of 2a with m-chloroperoxybenzoic acid produced the corresponding polyester 2b containing sulfoxide groups. Thermogravimetric analyses and visual observations indicated 2b to be thermally unstable relative to 2a and 2c .     

Polyesters from 2,6-dihydroxy-9,10-dihydro-9,10-ethanoanthracene and 2,6-dihydroxyanthracene

High molecular weight, film-forming, amorphous polyesters have been prepared from 2,6-dilydroxy-9,10-dihydro-9,10-ethanoanthracene with adipic, sebacic, dodecanoic, isophthalic, 4,4′-oxybibenzoic, 2,6-naphthoic, 4,4′-bibenzoic, and terephthalic acid. Thermal elimination of ethylene from these polymers has yielded the corresponding polyesters from 2,6-dihydroxyanthracene which were of high molecular weight, film forming, and crystalline.     

Functional Polymers. VIII. Polyesters from Hindered Bisphenols

It was demonstrated that highly hindered bisphenols could be used to produce polyesters of moderate molecular weight. Bisphenols linked in the 4 and 4′ or the 2 and 2′ positions and substituted in positions ortho and para to the phenolic hydroxyl groups with methyl or tertiary butyl groups (these bisphenols are now used as very effective antioxidants) formed polymers, their reactivity depending more on the nature of the group linking the two phenyl rings than on the steric effects of the ortho substi-tuents. Bisphenols linked in the 2 and 2′ positions and containing bulky electron-withdrawing groups were found to be least effective as condensation monomers although successful polymerization to moderate molecular weight could be achieved using me it polycondensation techniques.     

Hyperbranched Aromatic Polyesters

Summary: Having developed a theoretical model of hyperbranched polymerization involving AB₂ and B₂ monomers we present preliminary results of a test of its validity for the system consisting of 4,4-bis(4-hydroxyphenyl)pentanoic acid (AB₂ monomer) and bisphenol A (B₂ monomer). The monomers reacted at room temperature to yield the title hyperbranched polyesters. Diisopropylcarbodiimide (condensation water remover) along with an effective catalyst were used for that purpose. The total of AB₂ monomer was introduced at once to a reactor containing B₂ core monomer or it was divided into 3 or 5 equal portions and each of them introduced after the monomers previously present have reacted to a predetermined conversion. GPC measurements of the resulting molecular mass distribution gave inconclusive results because of poor reproducibility of polymer isolation/purification procedure and/or insufficient accuracy of GPC technique.     

Degradable and Recyclable Polyesters from Multiple Chain Length Bio- and Waste-Sourceable Monomers

Monomers sourced from waste or biomass are often mixtures of different chain lengths; e.g. catalytic oxidation of polyethylene waste yields mixtures of dicarboxylic acids (DCAs). Yet, polyesters synthesized from such monomer mixtures have rarely been studied. We report polyesters based on multiple linear aliphatic DCAs, present in chain length distributions that vary in their centers and ranges. We demonstrate that these materials can adopt high-density polyethylene-like solid state structures, and are ductile (e.g. E_t 610 MPa), allowing for injection molding, or film and fiber extrusion. Melting and crystallization points of the polyesters show no odd-even effects as dipoles cannot favorably align in the crystal, similar to traditional odd carbon numbered, long-chain DCA polyesters. Biodegradation studies of ¹³C-labelled polyesters in soil reveal rapid mineralization, and depolymerization by methanolysis indicates suitability for closed-loop recycling.     

Liquid Crystalline Aromatic Polyesters

The background to development of liquid crystalline aromatic polyesters is reviewed. Specific programs directed at the development of the homopolymer of p-hydroxybenzoic acid and copolymer with biphenol terephthalate are described. Work on novel processing techniques is highlighted in this paper while questions of synthesis, structure, and properties are considered somewhat more briefly.     

聚酯的生物改性

从四个方面综述了近年来聚对苯二甲酸乙二酯(PET)和聚对苯二甲酸丁二酯(PBT)生物改性的研究进展:(1)在聚酯合成中采用生物原料;(2)采用共聚技术制备可生物降解性共聚酯;(3)生物活性物质在聚酯中的引入改性,可提高其生物相容性和抗菌能力,在聚酯用于人造器官时,可使血管纤维原细胞的细胞增殖;(4)生物酶对聚酯进行水解改性,可减轻重量,并改善吸湿性、染色性等性能。     

Polyesters from Macrolactones Using Commercial Lipase NS 88011 and Novozym 435 as Biocatalysts

The demand for environmentally friendly products allied with the depletion of natural resources has increased the search for sustainable materials in chemical and pharmaceutical industries. Polyesters are among the most widely used biodegradable polymers in biomedical applications. In this work, aliphatic polyesters (from globalide and ω-pentadecalactone) were synthesized using a new commercial biocatalyst, the low-cost immobilized NS 88011 lipase (lipase B from Candida antarctica immobilized on a hydrophobic support). Results were compared with those obtained under the same conditions using a traditional, but more expensive, commercial biocatalyst, Novozym 435 (lipase B from C. antarctica immobilized on Lewatit VP OC). When NS 88011 was used in the polymerization of globalide, longer reaction times (240 min)—when compared to Novozym 435—were required to obtain high yields (80–90 wt%). However, higher molecular weights were achieved. When poly(ω-pentadecalactone) was synthesized, high yields and molecular weights (130,000 g mol^?1) were obtained and the enzyme concentration showed strong influence on the polyester properties. This is the first report describing NS 88011 in polymer synthesis. The use of this cheaper enzymatic preparation can provide an alternative for polyester synthesis via enzymatic ring-opening polymerization.     

Polyesters containing the norbornane structure

Several norbornane and norbornane condensed diesters and dimethanols have been synthesized. Varying the points of substitution in the norbornane moiety has been found to have little effect on the glass transition temperatures of polyesters prepared from these compounds. Increasing the number of norbornane residues as polymer side chains results in a linear increase in the T_g. The increase is an apparent function of the size of the norbornane moiety relative to the polymer repeating unit.     

脯氨酸聚酯的单链力学性质

脯氨酸聚酯(PPEs)是一类分子量较高且分子量分布较窄的新型可降解脂肪族聚酯,有巨大的应用潜力.然而,还没有关于PPEs力学性质的报道.本工作使用基于原子力显微镜的单分子力谱(AFM-based SMFS)实验技术和熵焓弹性耦合模型研究了PNC 12PE(一种PPEs)在极性有机溶剂中的力学性质.熵焓弹性耦合模型对PN...     

高支化聚酯的合成及表征

高支化聚酯的合成及表征;开环聚合;偏苯三酸酐;环氧氯丙烷     

Shape Memory Particles Capable of Controlled Geometric and Chemical Asymmetry made from Aliphatic Polyesters

A novel method for producing monodisperse micro‐ and nanosized shape memory particles from various shape memory polymers (SMPs) is reported. This method uses a polydimethylsiloxane mold to uniformly deform particles from complex shapes to other well‐defined shapes, harvest them without aggressive solvents or heat, and then return them to their original shapes upon heating above a preselected trigger temperature. By manipulating the material properties of both the mold and SMP, monodisperse asymmetric particles are easily achieved. This method is demonstrated with traditional SMPs and polymers with varying degrees of reactive functionality, crystallinity, and transition temperature. This additional reactivity and the robustness of this system allow easy tailoring of the surface with click chemistry to achieve chemical asymmetry.