High shearing rate method for spinning poly-terephthaloyl p-phenylenediamine fibre

Abstract

The invented method includes the following steps: uniformly mixing PPTA and concentrated sulfuric acid whose concentration is greater than 99% in mixing cylinder, preparing mixed solution in which PPTA content is 14%-24%; making the prepared PPTA mixed solution pass through twin screw extruder, further dissolving to form liquid crystal spinning solution, defoaming, fully mixing and regulating temperature, applying high shear stress to the defoamed PPTA spinning slurry in extruder machine head, filtering and metering, adopting dry-jet wet-spinning process to obtain the invented PPTA fibre.

Description

Technical field

[0001] The invention relates to a method for spinning polyparaphenylene terephthalamide (PPTA) fiber, in particular to a method for spinning polyparaphenylene terephthalamide (PPTA) fiber at a high shear rate. Background technique

[0002] Poly-p-phenylene terephthalamide fiber is a typical aromatic polyamide fiber, also known as para-aramid or PPTA fiber, with high strength and high modulus, high temperature resistance, low creep and other excellent physical machinery Performance is the fastest growing type of high-tech fiber in the field of fiber materials in recent years. It is mainly used in industrial textiles, especially for many products that require light weight and high performance. This type of fiber can only be used.

[0003] In the early 1970s, DuPont of the United States first disclosed the use of dry jet-wet spinning PPTA / H in patent USP 3,767,756 2 SO 4 Liquid crystal slurry, spun high-strength and high-modulus PPTA fiber, but there is PPTA / H 2 SO 4...

Examples

Embodiment 1

[0022] Add 1.43 kg of dry PPTA resin with an intrinsic viscosity of 6.5dl / g and 3.5 liters of 100% sulfuric acid into a 10 liter mixing cylinder. After mixing for 20 minutes at 85°C, the mixture is continuously extruded with a diameter of 55mm and a length of In a twin-screw extruder with a diameter ratio of 60 and a rotation speed of 30 rpm, the temperature of the twin screw is controlled to 85°C. The first half of the screw is 1400mm long and the second half is 1900mm long. The PPTA resin is completed in the twin screw at H 2 SO 4 To fully dissolve and remove bubbles in the spinning solution, after about 50 minutes, apply high shear stress to the spinning solution that is fully mixed, temperature-regulated, and bubbles out of the spinning solution at the head of the extruder. After filtering, After the metering pump, with 5.5×10 3 s -1 The shear rate is sent to the spinneret, the size of the spinneret is Φ0.08×300 holes, and the 5mm air gap layer enters the spinning tube of the ...

Embodiment 2

[0024] Add 1.43 kilograms of dry PPTA resin with an intrinsic viscosity of 4.5dl / g and 3.5 liters of 100% sulfuric acid into a 10 liter mixing cylinder. After mixing for 5 minutes at 85°C, the mixture is continuously extruded with a diameter of 25mm and a length of 25mm. In a twin-screw extruder with a diameter ratio of 30 and a rotating speed of 10 rpm, the temperature of the twin screw is controlled to 50°C. The first half of the screw is 1500mm long and the second half is 1750mm long. The PPTA resin is completed in the twin screw. 2 SO 4 To fully dissolve and remove bubbles in the spinning solution, after about 35 minutes, high shear stress is applied to the spinning solution that is fully mixed, well-adjusted, and bubbles are removed at the head of the extruder. After filtering, After the metering pump, with 4.5×10 5 s -1 The shear rate is sent to the spinneret, the size of the spinneret is Φ0.08×300 holes, through the 5mm air gap layer, into the coagulation bath spinning tube...

Embodiment 3

[0026] Add 1.43 kilograms of dry PPTA resin with an intrinsic viscosity of 8.5dl / g and 3.5 liters of 100% sulfuric acid into a 10-liter mixing cylinder. After mixing for 20 minutes at 85°C, the mixture is continuously extruded with a diameter of 145mm and a length of In a twin-screw extruder with a diameter ratio of 80 and a rotation speed of 200 rpm, the temperature of the twin screw is controlled to 100°C. The first half of the screw is 1400mm long and the second half is 1900mm long. The PPTA resin is completed in the twin screw. 2 SO 4 Dissolve and remove bubbles in the spinning solution. After about 3 minutes, apply high shear stress to the spinning solution that is fully mixed, well-adjusted, and bubbles are removed at the head of the extruder. After filtering, After the metering pump, with 1.0×10 3 s -1The shear rate is sent to the spinneret, the size of the spinneret is Φ0.08×300 holes, and the 5mm air gap layer enters the spinning tube of the coagulation bath. The temperat...

Technical field

[0001] The invention relates to a method for spinning polyparaphenylene terephthalamide (PPTA) fiber, in particular to a method for spinning polyparaphenylene terephthalamide (PPTA) fiber at a high shear rate. Background technique

[0002] Poly-p-phenylene terephthalamide fiber is a typical aromatic polyamide fiber, also known as para-aramid or PPTA fiber, with high strength and high modulus, high temperature resistance, low creep and other excellent physical machinery Performance is the fastest growing type of high-tech fiber in the field of fiber materials in recent years. It is mainly used in industrial textiles, especially for many products that require light weight and high performance. This type of fiber can only be used.

[0003] In the early 1970s, DuPont of the United States first disclosed the use of dry jet-wet spinning PPTA / H in patent USP 3,767,756 2 SO 4 Liquid crystal slurry, spun high-strength and high-modulus PPTA fiber, but there is PPTA / H 2 SO 4...

Examples

Embodiment 1

[0022] Add 1.43 kg of dry PPTA resin with an intrinsic viscosity of 6.5dl / g and 3.5 liters of 100% sulfuric acid into a 10 liter mixing cylinder. After mixing for 20 minutes at 85°C, the mixture is continuously extruded with a diameter of 55mm and a length of In a twin-screw extruder with a diameter ratio of 60 and a rotation speed of 30 rpm, the temperature of the twin screw is controlled to 85°C. The first half of the screw is 1400mm long and the second half is 1900mm long. The PPTA resin is completed in the twin screw at H 2 SO 4 To fully dissolve and remove bubbles in the spinning solution, after about 50 minutes, apply high shear stress to the spinning solution that is fully mixed, temperature-regulated, and bubbles out of the spinning solution at the head of the extruder. After filtering, After the metering pump, with 5.5×10 3 s -1 The shear rate is sent to the spinneret, the size of the spinneret is Φ0.08×300 holes, and the 5mm air gap layer enters the spinning tube of the ...

Embodiment 2

[0024] Add 1.43 kilograms of dry PPTA resin with an intrinsic viscosity of 4.5dl / g and 3.5 liters of 100% sulfuric acid into a 10 liter mixing cylinder. After mixing for 5 minutes at 85°C, the mixture is continuously extruded with a diameter of 25mm and a length of 25mm. In a twin-screw extruder with a diameter ratio of 30 and a rotating speed of 10 rpm, the temperature of the twin screw is controlled to 50°C. The first half of the screw is 1500mm long and the second half is 1750mm long. The PPTA resin is completed in the twin screw. 2 SO 4 To fully dissolve and remove bubbles in the spinning solution, after about 35 minutes, high shear stress is applied to the spinning solution that is fully mixed, well-adjusted, and bubbles are removed at the head of the extruder. After filtering, After the metering pump, with 4.5×10 5 s -1 The shear rate is sent to the spinneret, the size of the spinneret is Φ0.08×300 holes, through the 5mm air gap layer, into the coagulation bath spinning tube...

Embodiment 3

[0026] Add 1.43 kilograms of dry PPTA resin with an intrinsic viscosity of 8.5dl / g and 3.5 liters of 100% sulfuric acid into a 10-liter mixing cylinder. After mixing for 20 minutes at 85°C, the mixture is continuously extruded with a diameter of 145mm and a length of In a twin-screw extruder with a diameter ratio of 80 and a rotation speed of 200 rpm, the temperature of the twin screw is controlled to 100°C. The first half of the screw is 1400mm long and the second half is 1900mm long. The PPTA resin is completed in the twin screw. 2 SO 4 Dissolve and remove bubbles in the spinning solution. After about 3 minutes, apply high shear stress to the spinning solution that is fully mixed, well-adjusted, and bubbles are removed at the head of the extruder. After filtering, After the metering pump, with 1.0×10 3 s -1The shear rate is sent to the spinneret, the size of the spinneret is Φ0.08×300 holes, and the 5mm air gap layer enters the spinning tube of the coagulation bath. The temperat...