阅读说明：本技术 一种连续长丝束酚醛纤维的制备方法 (Preparation method of continuous filament bundle phenolic fiber ) 是由 刘占军 张东卿 李宏弟 宋燕 郭全贵 于 2019-08-30 设计创作，主要内容包括：本发明涉及一种连续长丝束酚醛纤维的制备方法,属于酚醛纤维制备方法技术领域,解决熔纺工艺在工程放大和规模化生产中存在的技术问题,解决方案为：利用热固性酚醛树脂受热进一步交联固化这一特点,将热固性酚醛树脂制备成纺丝原液,然后经过纺丝、凝固浴成型、牵伸得到酚醛树脂原丝,再经过加热交联固化后可得到酚醛纤维。本发明可制备出传统的熔纺工艺难以制备的长丝束酚醛纤维,同时还具有工艺连续、易于工程放大、节能、环保、对人员防护和设备防腐要求低等优点。(The invention relates to a preparation method of continuous filament bundle phenolic fiber, belonging to the technical field of phenolic fiber preparation methods, solving the technical problems of melt spinning process in engineering amplification and large-scale production, and the solution is as follows: by utilizing the characteristic that thermosetting phenolic resin is further crosslinked and cured by heating, the thermosetting phenolic resin is prepared into spinning solution, then the spinning solution, the coagulating bath forming and the drafting are carried out to obtain phenolic resin protofilaments, and the phenolic fibers can be obtained after the heating crosslinking and curing. The invention can prepare the long-tow phenolic fiber which is difficult to prepare by the traditional melt spinning process, and has the advantages of continuous process, easy engineering amplification, energy saving, environmental protection, low requirements on personnel protection and equipment corrosion prevention and the like.)

1. A method for preparing continuous filament phenolic fiber is characterized by comprising the following steps:

s1, preparing a spinning solution: preparing a spinning solution from a mixed solution of thermosetting phenolic resin and PVA, wherein the viscosity range of the prepared spinning solution is 5000-20000 mPa.s;

s2, preparing a coagulating bath solution: the coagulating bath solution is an aqueous solution consisting of a complexing crosslinking agent, a dehydrating agent and an acid-base neutralizing agent, wherein the content of the complexing crosslinking agent is 1-6wt%, the concentration of the acid-base neutralizing agent is 1-5wt%, and the dehydrated content agent is the concentration of the aqueous solution in a near-saturated state;

s3, drawing and solidifying: drafting the spinning solution prepared in the step S1 in the coagulating bath solution prepared in the step S2, wherein the drafting coagulation process is 3-7 sections, and the total drafting multiple is 3-15 times;

s4, heating, curing and crosslinking of the fiber: and (5) washing and drying the fiber drafted in the step S3, heating, curing and crosslinking at the curing and crosslinking temperature of 100-180 ℃ for 10-200 minutes, oiling and collecting the fiber to obtain the continuous filament beam phenolic fiber.

2. The method of making a continuous filament tow phenolic fiber according to claim 1, wherein: in step S2, the complex crosslinking agent includes boric acid or a borate, and the borate is one or more of calcium borate, sodium borate, magnesium borate and potassium borate.

3. The method of making a continuous filament tow phenolic fiber according to claim 1, wherein: in the step S2, the dehydrating agent is one or more of magnesium sulfate, sodium sulfate, copper sulfate and calcium chloride.

4. The method of making a continuous filament tow phenolic fiber according to claim 1, wherein: in step S2, the acid-base neutralization reagent is one of hydrochloric acid, sulfuric acid, and phosphoric acid.

Technical Field

The invention relates to a preparation method of continuous filament bundle fibers, in particular to a novel process for preparing the filament bundle phenolic fibers by spinning a phenolic resin solution.

Background

The phenolic fiber is a special fiber integrating multiple functions of temperature resistance, heat insulation, flame retardance, corrosion resistance, sound insulation and the like. The flame-retardant coating has wide application prospect in the application fields of flame retardance, high-temperature thermal protection, heat preservation and insulation, sound insulation, chemical protection, high-grade indoor flame-retardant decorative materials such as airplanes and submarines and the like, and is monopolized by Kynol company internationally.

At present, the production process of phenolic fiber manufacturers and the test process of scientific research institutions are both focused on the melt spinning process, and due to the limitation of the process method and the structural characteristics of resin, the melt spinning is only suitable for preparing chopped fibers with certain length, and the prepared fibers have lower performance. Although the phenolic fiber prepared by the melt spinning process is improved in multiple ways, the phenolic fiber is still brittle, poor in toughness and low in mechanical property, certain difficulty is brought to the subsequent spinning and weaving process, and the yield is low; the main application of phenolic fibers has been focused on fiber fabrics. Meanwhile, melt spinning of the phenolic fiber can be carried out separately, and continuous production cannot be realized; and the high-temperature and high-concentration hydrochloric acid and formaldehyde solution exist in the curing process, so that serious pollution and corrosion are caused. The process has certain drawbacks and limitations in fiber performance, continuous filament preparation, process continuity, engineering scale-up and environmental protection.

Disclosure of Invention

In order to overcome the defects in the prior art and solve the technical problems of the melt spinning process in engineering amplification and large-scale production, the invention provides a preparation method of continuous filament bundle phenolic fibers.

The design concept of the invention is as follows: the wet spinning process of phenolic fiber is to utilize the characteristic that thermosetting phenolic resin is heated to further react and crosslink, prepare the resin into spinning solution, then obtain phenolic resin protofilament through spinning, coagulating bath forming and drafting, and obtain phenolic fiber after heating, crosslinking and curing.

The invention is realized by the following technical scheme.

A method for preparing continuous filament phenolic tow fibers comprises the following steps:

s1, preparing a spinning solution: preparing a spinning solution from a mixed solution of thermosetting phenolic resin and PVA, wherein the viscosity range of the prepared spinning solution is 5000-20000 mPa.s;

s2, preparing a coagulating bath solution: the coagulating bath solution consists of a complexing crosslinking agent, a dehydrating agent, an acid-base neutralizing agent and water;

the complexing crosslinking agent mainly comprises boric acid or borate such as calcium borate, sodium borate, magnesium borate, potassium borate and the like, and the content is 1-6 wt%;

the dehydrating agent mainly comprises inorganic salts with dehydrating effect such as magnesium sulfate, sodium sulfate, copper sulfate, calcium chloride and the like, and the content is the concentration of the aqueous solution in a near saturated state;

the acid-base neutralizing agent mainly comprises inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and the like, and the concentration is 1-5 wt%;

s3, drawing and solidifying: drafting the spinning solution prepared in the step S1 in the coagulating bath solution prepared in the step S2, wherein the drafting coagulation process is 3-7 sections, and the total drafting multiple is 3-15 times;

s4, heating, curing and crosslinking of the fiber: and (5) washing and drying the fiber drafted in the step S3, heating, curing and crosslinking at the curing and crosslinking temperature of 100-180 ℃ for 10-200 minutes, oiling and collecting the fiber to obtain the continuous filament beam phenolic fiber.

The invention has the following beneficial effects:

the preparation method of the continuous filament bundle phenolic fiber provided by the invention can be used for directly preparing the continuous filament bundle phenolic fiber, has good continuity between sections, and can realize continuous production of the process; and high-pollution and high-corrosiveness chemical reagents do not exist, and the requirements on personnel protection and equipment corrosion prevention are low. Meanwhile, the spinning section of the invention has no high-temperature melting process, the high-temperature curing and crosslinking time is greatly shortened, and the energy-saving effect is obvious.

Detailed Description

The present invention will be described in further detail with reference to examples.