US-20260125549-A1 - TRANSPARENT FLAME-RETARDANT SHEET HAVING HIGH CHLORINE CONTENT AND POLYVINYL CHLORIDE COMPOSITION THEREOF

US20260125549A1US 20260125549 A1US20260125549 A1US 20260125549A1US-20260125549-A1

Abstract

A transparent flame-retardant sheet having a high chlorine content is provided. The transparent flame-retardant sheet is made of a polyvinyl chloride composition that includes 100 parts by weight of a polyvinyl chloride raw material component, 0.1 to 1 parts by weight of at least one carbon forming agent, and 2 to 5 parts by weight of at least one heat stabilizer. The polyvinyl chloride raw material component includes a polyvinyl chloride raw material and a chlorinated polyvinyl chloride raw material in a content ratio of 1:1.22 to 1:4. Therefore, the transparent flame-retardant sheet has a fire propagation index (FPI) of less than 6 and a smoke damage index (SDI) of less than 0.4 according to the FM4910 standard under the condition of having a thickness of 5 mm.

Inventors

Ching-Yao Yuan
Chun-Che Tsao
Ci-Syuan Liou

Assignees

NAN YA PLASTICS CORPORATION

Dates

Publication Date: 20260507
Application Date: 20241230
Priority Date: 20241107

Claims (10)

1 . A polyvinyl chloride composition for manufacturing a transparent flame-retardant sheet having a high chlorine content, comprising: 100 parts by weight of a polyvinyl chloride raw material component including a polyvinyl chloride raw material and a chlorinated polyvinyl chloride raw material in a content ratio of 1:1.22 to 1:4; 0.1 to 1 parts by weight of at least one carbon forming agent; and 2 to 5 parts by weight of at least one heat stabilizer; wherein the transparent flame-retardant sheet, under the condition of having a thickness of 5 mm, has a chlorine content from 52% to 60%, a transmittance of not less than 60%, and a haze of not more than 10%, and has a fire propagation index (FPI) of less than 6 and a smoke damage index (SDI) of less than 0.4 according to the FM4910 standard.
2 . The polyvinyl chloride composition according to claim 1 , wherein the at least one carbon forming agent is selected from the group consisting of phosphate ester, a phosphazene compound, ammonium polyphosphate, melamine, dicyandiamide, hydrotalcite, and zinc oxide.
3 . The polyvinyl chloride composition according to claim 2 , wherein the at least one carbon forming agent is the combination of the phosphate ester and the zinc oxide, and a content ratio of the phosphate ester to the zinc oxide is 1:2 to 2:1.
4 . The polyvinyl chloride composition according to claim 1 , wherein the at least one heat stabilizer is selected from the group consisting of organotins, metallic soaps, and lead salts.
5 . The polyvinyl chloride composition according to claim 4 , wherein the at least one heat stabilizer is the combination of butyltin mercaptide and calcium zinc stabilizer, and a content of the butyltin mercaptide is greater than a content of the calcium zinc stabilizer.
6 . The polyvinyl chloride composition according to claim 1 , further comprising 2.5 to 6 parts by weight of at least one impact modifier.
7 . The polyvinyl chloride composition according to claim 1 , wherein the at least one impact modifier is selected from the group consisting of methyl methacrylate-butadiene-styrene copolymer (MBS), an acrylate copolymer, ethylene-vinyl acetate copolymer (EVA), and styrene-ethylene-butylene-styrene copolymer (SEBS).
8 . The polyvinyl chloride composition according to claim 7 , wherein the at least one impact modifier is the combination of the MBS and the acrylate copolymer, and a content of the MBS is greater than a content of the acrylate copolymer.
9 . The polyvinyl chloride composition according to claim 1 , further comprising at least one processing aid that includes a plasticizer, a slip agent, a gelling accelerator, a colorant, an antioxidant, and/or a UV absorber.
10 . A transparent flame-retardant sheet having a high chlorine content made of the polyvinyl chloride composition as claimed in claim 1 , wherein the transparent flame-retardant sheet has a chlorine content from 52% to 60%, a transmittance of not less than 60%, and a haze of not more than 10%, and has a fire propagation index (FPI) of less than 6 and a smoke damage index (SDI) of less than 0.4 according to the FM4910 standard under the condition of having a thickness of 5 mm.

Description

CROSS-REFERENCE TO RELATED PATENT APPLICATION This application claims the benefit of priority to Taiwan Patent Application No. 113142659, filed on Nov. 7, 2024. The entire content of the above identified application is incorporated herein by reference. Some references, which may include patents, patent applications and various publications, may be cited and discussed in the description of this disclosure. The citation and/or discussion of such references is provided merely to clarify the description of the present disclosure and is not an admission that any such reference is “prior art” to the disclosure described herein. All references cited and discussed in this specification are incorporated herein by reference in their entireties and to the same extent as if each reference was individually incorporated by reference. FIELD OF THE DISCLOSURE The present disclosure relates to a plastic sheet, and more particularly to a transparent flame-retardant sheet having a high chlorine content and a polyvinyl chloride composition thereof. BACKGROUND OF THE DISCLOSURE Polyvinyl chloride (PVC) has good performance in flame resistance, chemical resistance, transparency, mechanical strength, electrical insulation, and processability, and has become one of the most widely used plastic materials and can be used in the manufacture of film, sheet, pipe, and wire insulation. However, most of the plasticizers in PVC products are flammable and can produce a large amount of smoke when PVC products burn, making escape and rescue difficult. The application scope of PVC materials in semiconductor factories and electronics factories continues to expand, such as ceilings, partition screens, and process, air flow control, and ventilation equipment of the cleanroom. If flame retardance and smoke suppression cannot be effectively performed in the event of a fire, the spread of fire and large amounts of harmful smoke may cause great losses. Therefore, how to improve the flame retardant and smoke suppression performance of PVC products has become an important issue in the related industries. Although flame retardants and smoke inhibitors can be added to PVC materials to achieve certain flame retardant and smoke suppression effects, material processability and product mechanical properties may be negatively affected, and products cannot satisfy the high transparency requirement in practical applications. SUMMARY OF THE DISCLOSURE One aspect of the present disclosure is that polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) raw materials are used in combination in a specific ratio, and at least one carbon forming agent is added to a resulting PVC/CPVC blend system to produce synergistic effects, such that a finished sheet has not only high flame retardancy and low smoke emission but also a high transmittance and a low haze. In response to the above-referenced technical inadequacies, the present disclosure provides a transparent flame-retardant sheet having a high chlorine content and a polyvinyl chloride composition thereof. In order to solve the above-mentioned problems, one of the technical aspects adopted by the present disclosure is to provide a polyvinyl chloride composition for manufacturing a transparent flame-retardant sheet having a high chlorine content. The polyvinyl chloride composition includes 100 parts by weight of a polyvinyl chloride raw material component, 0.1 to 1 parts by weight of at least one carbon forming agent, and 2 to 5 parts by weight of at least one heat stabilizer. The polyvinyl chloride raw material component includes a polyvinyl chloride raw material and a chlorinated polyvinyl chloride raw material in a content ratio of 1:1.22 to 1:4. The transparent flame-retardant sheet, under the condition of having a thickness of 5 mm, has a chlorine content from 52% to 60%, a transmittance of not less than 60%, and a haze of not more than 10%, and has a fire propagation index (FPI) of less than 6 and a smoke damage index (SDI) of less than 0.4 according to the FM4910 standard. In one of the possible or preferred embodiments, the at least one carbon forming agent is selected from the group consisting of phosphate ester, a phosphazene compound, ammonium polyphosphate, melamine, dicyandiamide, hydrotalcite, and zinc oxide. In one of the possible or preferred embodiments, the at least one carbon forming agent is the combination of the phosphate ester and the zinc oxide, and a content ratio of the phosphate ester to the zinc oxide is 1:2 to 2:1. In one of the possible or preferred embodiments, the at least one heat stabilizer is selected from the group consisting of organotins, metallic soaps, and lead salts. In one of the possible or preferred embodiments, the at least one heat stabilizer is the combination of butyltin mercaptide and calcium zinc stabilizer, and a content of the butyltin mercaptide is greater than a content of the calcium zinc stabilizer. In one of the possible or preferred embodiments, the