摘要:
Described herein is a feasible, significantly simplified production method that avoids challenging lactonization steps and converts a low molecular weight aliphatic polyester, consisting of hydroxy acids and a comonomer, whose molecular weight has been increased by step-growth polymerization reactions. The molecular weight of the aliphatic polyester, based on comparison of initial and final weight average molecular weights (Mw,1/Mw,2), increased significantly at a rate which permits the use of reactive extrusion to produce high molecular weight aliphatic polyesters in a simple, economically feasible manner.
摘要:
Solid-state shear pulverization of semi-crystalline polymers and copolymers thereof and related methods for enhanced crystallization kinetics and physical/mechanical properties.
摘要:
The present invention relates to a continuous process for heat treatment of a particulate thermoplastic material comprising a thermoplastic semi-crystalline polymer in the solid state in a single flow-through installation comprising one or more heating zones, wherein each heating zone comprises a contact heater consisting of an array of heating plates, the granulate material is transported as a moving packed bed in the flow-through installation, the process comprises one or more heating steps and in each heating step the particulate material is heated through contact heating via the contact heater, or one of the contact heaters, and optionally a flow of inert gas is applied in one or more heating zones with a mass ratio G/M of at most 2, wherein G is the inert gas flow in kg/hour and M is the particulate material flow in kg/hour.
摘要:
Disclosed are compositions and methods that provide flexible transparent conductive films that exhibit low levels of oligomer migration and haze development, without making use of costly substrates based on PEN film or PET films having low oligomer content. Such flexible transparent conductive films are useful in electronic and optical applications.
摘要:
The invention relates to a method for producing a semicrystalline polymer, said method comprising the following steps: producing a polymer melt from a crystallizable polymer; shaping particles and solidifying the polymer melt, the step of shaping the particles being carried out before or after solidification; cooling the particles; treating the particles to reduce their tendency to agglomerate; crystallizing the particles. The invention is characterized in that the treatment is carried out by shaking at a temperature T1 which is below the glass transition temperature of the polymer plus 10° C., i.e. T1
摘要:
An apparatus for continuous pelletization and crystallization of a polymer includes a unit for forming a polymer pellet material and cooling the pellet material in a liquid cooling medium. An after-connected drying unit has an exit opening for exporting gas and a crystallizer for crystallizing the pellet material. The crystallizer communicates via a connection line with the pre-connected unit for separating the liquid cooling medium from the pellet material and drying the pellet material. The crystallizer communicates with an inert gas tank, whereby the pressure in the crystallizer can be increased relative to the pressure in the drying unit. A related process is also disclosed.
摘要:
The invention provides biodegradable aliphatic polyester particles having the following physical properties: (A) the average particle diameter thereof is 5 to 500 μm; and (B) the fracture stress of a columnar tablet obtained by molding the particles in a cylindrical mold by applying a load of 4 kgf/cm2 for 1 hour at a temperature of 40° C. is at most 500 gf/cm2, and preferably also having the following property: (C) the fracture stress of a columnar tablet obtained by molding the particles in a cylindrical mold by applying a load of 4 kgf/cm2 for 1 hour at a temperature of [the glass transition temperature (Tg) of a biodegradable aliphatic polyester +10° C.] is at most 2,000 gf/cm2, a process for producing the biodegradable aliphatic polyester particles, which comprises treating a particulate biodegradable aliphatic polyester obtained by grinding at a temperature lower than the Tg at a temperature not lower than [the crystallization temperature (Tc1) upon heating of the biodegradable aliphatic polyester−40° C], and the biodegradable aliphatic polyester particles obtained by the production process.
摘要翻译:本发明提供具有以下物理性质的生物可降解脂族聚酯颗粒:(A)其平均粒径为5至500μm; 和(B)通过在40℃的温度下施加4kgf / cm 2的负荷1小时将通过在圆筒形模具中成型颗粒而获得的柱状片的断裂应力为500gf / cm 2以下,优选为 还具有以下特性:(C)通过在[玻璃化转变温度(Tg)为[玻璃化转变温度(Tg)]的温度下,通过在4kgf / cm 2的负荷下进行1小时的模塑而将颗粒成形为圆柱形模具而获得的柱状片的断裂应力 生物降解性脂肪族聚酯+ 10℃]为2000gf / cm 2以下,生物降解性脂肪族聚酯粒子的制造方法,其特征在于,在不低于Tg的温度下,在不低于Tg的温度下,研磨得到的颗粒状生物降解性脂肪族聚酯 低于[生物降解性脂肪族聚酯-40℃加热时的结晶温度(Tc1)],以及通过该制造方法得到的生物降解性脂肪族聚酯粒子。
摘要:
A method for carrying out polymerization processes, includes a first step involving polymerization or co-polymerization of a monomer or monomers, and a second step involving a separation step. In an embodiment, before the separation step, during the separation step, or both before and during the separation step, one or more substance is added to the reaction mixture that induces stripping, influencing of the temperature, or both stripping and influencing of the temperature such that the reaction equilibrium is shifted to the polymers and the rate of reaction to the monomer is slowed. In embodiments, before and/or in the second step, a substance is added to the reaction mixture so that a stop is achieved, and as a further function stripping and/or influencing of temperature occurs.
摘要:
Method and apparatus for thermally processing polyester pellets, e.g., polyethylene terephthalate pellets, in order to achieve a partial crystallization, whereby the polyester melt is fed to an underwater pelletizer and pelletized, the pellets obtained are fed to a water/solids separating device and the dried pellets are fed at a pellet temperature of greater than 100°C. to an agitation device that the pellets leave at a pellet temperature of over 100°C.
摘要:
Disclosed are compositions and methods that provide flexible transparent conductive films that exhibit low levels of oligomer migration and haze development, without making use of costly substrates based on PEN film or PET films having low oligomer content. Such flexible transparent conductive films are useful in electronic and optical applications.