WO2023179043A1 - 一种交联聚乙烯电缆绝缘材料可靠性预测方法 - Google Patents

一种交联聚乙烯电缆绝缘材料可靠性预测方法 Download PDF

Info

Publication number
WO2023179043A1
WO2023179043A1 PCT/CN2022/130863 CN2022130863W WO2023179043A1 WO 2023179043 A1 WO2023179043 A1 WO 2023179043A1 CN 2022130863 W CN2022130863 W CN 2022130863W WO 2023179043 A1 WO2023179043 A1 WO 2023179043A1
Authority
WO
WIPO (PCT)
Prior art keywords
cross
linked polyethylene
several groups
cable insulation
linking reaction
Prior art date
Application number
PCT/CN2022/130863
Other languages
English (en)
French (fr)
Inventor
侯帅
傅明利
黎小林
展云鹏
朱闻博
惠宝军
冯宾
张逸凡
Original Assignee
南方电网科学研究院有限责任公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 南方电网科学研究院有限责任公司 filed Critical 南方电网科学研究院有限责任公司
Publication of WO2023179043A1 publication Critical patent/WO2023179043A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N25/00—Investigating or analyzing materials by the use of thermal means
    • G01N25/20—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity
    • G01N25/48—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity on solution, sorption, or a chemical reaction not involving combustion or catalytic oxidation
    • G01N25/4846—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity on solution, sorption, or a chemical reaction not involving combustion or catalytic oxidation for a motionless, e.g. solid sample

Definitions

  • This application belongs to the field of cable technology, and in particular relates to a method for predicting the reliability of cross-linked polyethylene cable insulation materials.
  • cross-linked polyethylene insulation materials are widely used as insulation materials for long-distance overhead transmission lines and insulation materials for urban underground cables.
  • the preparation method of cross-linked polyethylene is to use active free radicals generated by the decomposition of the cross-linking agent to connect linear molecular chains into a cross-linked polyethylene insulation material with a network structure and excellent electrical properties.
  • the cross-linking agent serves as cross-linkable particles. Before the materials are put into the production of cross-linked polyethylene cable insulation, the cross-linking agent will spontaneously decompose due to storage temperature and storage time. Cross-linking agents such as dicumyl peroxide need to be stored under low temperature and dark light conditions, and their decomposition half-life decreases exponentially as the temperature increases.
  • cross-linked pellets under different storage conditions will affect the cross-linking degree of the cross-linking reaction, and the elongation under load of cross-linked polyethylene is closely related to its cross-linking degree, that is, cross-linked pellets under different storage conditions
  • the elongation under load of cross-linked polyethylene prepared from different materials is different.
  • this application provides a method for predicting the reliability of cross-linked polyethylene cable insulation materials by calculating the enthalpy value of the exothermic peak of the cross-linking reaction of the cross-linkable material, and using this enthalpy value to correlate with the polyethylene cable
  • the negative correlation between the elongation under load of the insulation layer material can be used to determine the elongation under load of the polyethylene cable insulation material, thereby quickly predicting the reliability of the cross-linked polyethylene cable insulation material and solving the lack of cross-linked polyethylene cable insulation material in the existing technology.
  • the first aspect of this application provides a method for predicting the reliability of cross-linked polyethylene cable insulation materials, which includes the following steps:
  • Step 1 Several groups of cross-linkable materials are subjected to cross-linking reactions to obtain the heat enthalpy values of the exothermic peaks of the cross-linking reactions of several groups of cross-linked polyethylene and several groups of cross-linkable materials;
  • Step 2 Conduct thermal extension experiments on several groups of cross-linked polyethylene to obtain the elongation under load of several groups of cross-linked polyethylene;
  • Step 3 Establish a reliability prediction curve for cross-linked polyethylene cable insulation materials based on the enthalpy values of the cross-linking reaction exothermic peaks of several groups of cross-linkable materials and the elongation under load of several groups of cross-linked polyethylene;
  • Step 4 The material to be predicted to be cross-linked undergoes a cross-linking reaction, and the enthalpy value of the material to be predicted to be cross-linked at the exothermic peak of the cross-linking reaction is obtained;
  • Step 5 Compare the enthalpy value of the cross-linkable material to be predicted at the exothermic peak of the cross-linking reaction with the standard enthalpy value;
  • the cross-linkable material contains a cross-linking agent and polyethylene.
  • step 5 it also includes:
  • Step 6 The heat enthalpy value of the exothermic peak of the cross-linking reaction of the cross-linkable material to be predicted is input into the reliability prediction curve of the cross-linked polyethylene cable insulation material, and the elongation under load of the cross-linked polyethylene to be predicted is obtained;
  • Step 7 Compare the elongation under load of the cross-linked polyethylene to be predicted with the standard value.
  • the standard value described in this application can be the standard value of elongation under load ( ⁇ 100%) of the XLPE material for 220kV cable insulation specified in the thermal elongation experiment part of GB/T 18890.2-2015, or It can be customized or other standard values defined in national standards.
  • the standard value of heat enthalpy in this application is 8.08655J/g.
  • the reliability prediction curve of cross-linked polyethylene cable insulation material is a prediction curve of elongation under load of cross-linked polyethylene.
  • the method for establishing the prediction curve of elongation under load of cross-linked polyethylene is to establish the thermal enthalpy value as the abscissa and the elongation under load of cross-linked polyethylene as the ordinate.
  • cross-linkable materials undergo a cross-linking reaction to obtain several groups of cross-linked polyethylene and several groups of cross-linkable materials.
  • the heat enthalpy values of the exothermic peaks of the cross-linking reaction include:
  • obtaining the enthalpy values of the exothermic peaks of the cross-linking reaction of several groups of cross-linkable materials includes: obtaining the cross-links of several groups of cross-linkable materials through the integrated area of the heat flow-time image of a differential scanning calorimeter. The enthalpy value of the exothermic peak of the reaction.
  • the calculation method of the integrated area of the heat flow-time image is as follows: taking the heat flow image before the exothermic peak of the cross-linking reaction as the baseline, and taking the tangent point between the baseline and the heat flow curve as the upper and lower limits of integration.
  • the cross-linking agent is peroxide.
  • the peroxide is dicumyl peroxide (DCP).
  • DCP dicumyl peroxide
  • cross-linkable materials undergo cross-linking reactions in a differential scanning calorimeter, including:
  • cross-linkable materials are put into a differential scanning calorimeter to perform a cross-linking reaction, including: after purging the differential scanning calorimeter with nitrogen, 5 mg to 10 mg are placed in a size of 0.5 mm ⁇ 0.5 mm ⁇ 0.5 mm.
  • groups of cross-linkable materials are cross-linked in special crucibles for differential scanning calorimeters.
  • the purity of the nitrogen is greater than 99.999%.
  • this application provides a method for predicting the reliability of cross-linked polyethylene cable insulation materials.
  • the prediction method includes: first performing cross-linking reactions on several groups of cross-linkable materials to obtain several groups of cross-linked polyethylene and several groups of The heat enthalpy value of the exothermic peak of the cross-linking reaction of the cross-linkable material is then established, and a reliability prediction curve of the cross-linked polyethylene cable insulation material is established.
  • the heat enthalpy value of the cross-linking reaction exothermic peak of the cross-linkable material to be predicted is obtained and Input the reliability prediction curve of cross-linked polyethylene cable insulation material to obtain the elongation under load of cross-linked polyethylene; among them, during the cross-linking reaction process of several groups of cross-linkable materials, the cross-linkable material pellets first absorb heat violently. As the polyethylene resin melts, the cross-linking agent DCP gradually decomposes. When the temperature further increases, the cross-linking reaction begins. A relatively weak exothermic peak of the cross-linking reaction appears in the heat flow curve, and its intensity is positively related to the degree of completion of the cross-linking reaction.
  • cross-linkable materials can be evaluated by calculating the enthalpy value of the exothermic peak of the cross-linking reaction during the heating process, and cross-linkable materials with different activities will affect the cross-linking degree of the cross-linking reaction.
  • the elongation under load of cross-linked polyethylene is closely related to its degree of cross-linking and is proportional to the relationship. That is, the lower the activity of cross-linked pellets, the greater the elongation under load of cross-linked polyethylene.
  • this application determines the polyethylene cable insulation by calculating the enthalpy value of the cross-linking agent at the exothermic peak of the cross-linking reaction and utilizing the negative correlation between the enthalpy value of the cross-linking agent and the elongation of the polyethylene cable insulation material under load.
  • the elongation rate of the material under load When the elongation rate under load is lower than the standard value, it is judged that the cross-linked polyethylene cable insulation material prepared with this cross-linked polyethylene is unreliable. There is no need to conduct experiments such as thermal extension again, and it can be quickly predicted
  • the reliability of cross-linked polyethylene cable insulation materials solves the technical problem of the lack of reliability prediction methods for cross-linked polyethylene cable insulation materials in the existing technology.
  • Figure 1 is a schematic flow chart of a method for predicting the reliability of cross-linked polyethylene cable insulation materials provided in Embodiment 3 of the present application;
  • Figure 2 is a schematic diagram of the calculation method for the enthalpy value of the cross-linkable material at the exothermic peak of the cross-linking reaction provided in Example 1 of the present application;
  • Figure 3 is a schematic diagram of establishing a reliability prediction curve for cross-linked polyethylene cable insulation material in Example 2 of the present application.
  • This application provides a method for predicting the reliability of cross-linked polyethylene cable insulation materials.
  • the heat enthalpy value of the exothermic peak of the cross-linking reaction of the cross-linkable material are used.
  • the relationship between the elongation under load and the elongation under load of the polyethylene cable insulation material can be determined, thereby quickly predicting the reliability of the cross-linked polyethylene cable insulation material, and solving the lack of reliability of the cross-linked polyethylene cable insulation material in the existing technology.
  • Technical issues with forecasting methods are used.
  • the reagents or raw materials used in the following examples are all commercially available or homemade.
  • This Example 1 provides a method for calculating the enthalpy value of the cross-linkable material in the exothermic peak of the cross-linking reaction, which includes the following steps:
  • the experimental program includes two temperature rise processes (confirm the first experimental effect through the second temperature rise), During the two heating processes, the temperature was raised from 30°C to 220°C, with a heating rate of 10°C/min. The heat flow through the sample and the heat flow through the empty crucible were measured during the heating process, and finally the heat flow through the cross-linkable material itself was obtained;
  • the sample mass should be weighed accurately to 0.01mg, and the mass difference between new pellets and stored pellets should be less than 5%; at the same time, the nitrogen (purity ⁇ 99.999%) purging environment must be ensured when the DSC experimental instrument is working to ensure that Avoid the oxidation reaction of the sample during the heating, melting and cooling crystallization processes, which will affect the experimental accuracy. If the exothermic enthalpy of the cross-linking reaction calculated from the heat flow curve of the same sample during the second heating process is greater than 0.1J/g, it means that the cross-linkable material in the sample was not cross-linked during the first heating process. Sufficient, the experiment needs to be repeated.
  • This Example 2 provides an example of establishing a reliability prediction curve for cross-linked polyethylene cable insulation materials based on the enthalpy value of the exothermic peak of the cross-linking reaction and the elongation under load of the cross-linked material:
  • Step 1 Cross-link the new pellets and 220kV high-voltage cross-linked cable insulation layer cross-linkable materials stored for one year, five years and ten years in a differential scanning calorimeter to obtain new pellets and stored
  • the cross-linking reaction exothermic peaks of cross-linked polyethylene and new pellets made from cross-linkable materials stored for one year, five years and ten years, and cross-linked materials stored for one year, five years and ten years.
  • Thermal enthalpy value wherein, the calculation of the thermal enthalpy value of the cross-linking material at the exothermic peak of the cross-linking reaction refers to Example 1, and the specific values see Table 1;
  • Step 2 Conduct thermal extension experiments on new pellets, cross-linked polyethylene prepared from cross-linkable materials stored for one year, five years and ten years in accordance with the national standard GB/T 18890.2-2015. See Table 2 for specific values;
  • the heat The enthalpy value has a negative correlation with the elongation of cross-linked polyethylene under load, so that the enthalpy value of the cross-linked material at the exothermic peak of the cross-linking reaction can be related to several
  • the elongation under load of cross-linked polyethylene is used to establish a reliability prediction curve for cross-linked polyethylene cable insulation materials. Based on existing experimental data, the reliability prediction curve shown in Figure 3 can be obtained. It can be seen from Figure 3 that the elongation and enthalpy value of cross-linked polyethylene under load should conform to a linear relationship. The characteristic equations of elongation and enthalpy value under load can be obtained through curve fitting.
  • the horizontal dotted line in the figure is the standard line of 100% elongation under load, and its intersection with the fitted straight line in the figure is 8.08655J/g. Therefore, it can be considered that in this example, when the exothermic enthalpy value of the cross-linking reaction measured by the cross-linkable material is greater than 8.08655J/g, the activity of the cross-linkable material still meets the required performance requirements, and the cross-linkable material prepared therefrom The reliability of polyethylene cable insulation materials complies with national standards.
  • This Embodiment 3 provides a method for predicting the reliability of cross-linked polyethylene cable insulation materials: including the following steps:
  • Step 1 Cross-linking reactions are carried out with new pellets, cross-linkable materials stored for one year, five years of storage and ten years of storage, and the heat enthalpy values of the exothermic peaks of the cross-linking reactions of four groups of cross-linked polyethylene and cross-linkable materials are obtained.
  • the calculation of the enthalpy value of the cross-linking material at the exothermic peak of the cross-linking reaction refers to Example 1, and the specific values are shown in Table 1;
  • Step 2 Conduct thermal extension experiments on new pellets, cross-linked polyethylene stored for one year, five years of storage and ten years of storage to obtain the load-down stretch of cross-linked polyethylene stored for one year, five years of storage and ten years of storage.
  • the specific value of elongation under load is shown in Table 2.
  • Step 3 Establish a reliability prediction curve for cross-linked polyethylene cable insulation materials based on the enthalpy values of the cross-linking reaction exothermic peaks of several groups of cross-linkable materials and the elongation under load of several groups of cross-linked polyethylene; where, the heat enthalpy The value has a negative correlation with the elongation under load of cross-linked polyethylene, so it can be based on the enthalpy value of the cross-linking reaction exothermic peak of new pellets, storage for one year, storage for five years, and storage for ten years.
  • the elongation under load of several groups of cross-linked polyethylene is used to establish a reliability prediction curve for cross-linked polyethylene cable insulation materials.
  • Step 4 The material to be predicted to be cross-linked undergoes a cross-linking reaction to obtain the enthalpy value of the material to be predicted to be cross-linked at the exothermic peak of the cross-linking reaction; where the material to be predicted to be cross-linked can be stored for any time, at any temperature or other Cross-linked material under storage conditions.
  • Step 5 The heat enthalpy value of the exothermic peak of the cross-linking reaction of the cross-linkable material to be predicted is input into the reliability prediction curve of the cross-linked polyethylene cable insulation material, and the elongation under load of the cross-linked polyethylene to be predicted is obtained;
  • the pellets absorb heat violently, causing an obvious endothermic peak to appear in the DSC heat flow curve.
  • the polyethylene resin in the cross-linkable material melts and the cross-linking agent DCP gradually decomposes.
  • the cross-linking reaction begins, and a relatively weak exothermic peak of the cross-linking reaction appears in the heat flow curve. Strength is positively related to the degree of completion of the cross-linking reaction.
  • the degree of cross-linking can be evaluated by calculating the enthalpy value of the exothermic peak of the cross-linking reaction of different cross-linkable materials during the heating process, and then the thermal extension performance of the XLPE material can be predicted.
  • this The invention proposes to use DSC experiments to connect the exothermic enthalpy of the cross-linking reaction of the cross-linkable material with the thermal elongation performance of the XLPE material, thereby enabling the reliability of cross-linked polyethylene to be predicted flexibly and quickly.

Abstract

一种交联聚乙烯电缆绝缘材料可靠性预测方法，包括以下步骤：步骤1、若干组可交联料进行交联反应，得到若干组交联聚乙烯和若干组可交联料的交联反应放热峰的热焓值；步骤2、若干组交联聚乙烯进行热延伸实验，得到若干组交联聚乙烯负载下伸长率；步骤3、基于若干组可交联料的交联反应放热峰的热焓值与若干组交联聚乙烯负载下伸长率建立交联聚乙烯电缆绝缘材料可靠性预测曲线；步骤4、待预测可交联料进行交联反应，得到待预测可交联料在交联反应放热峰的热焓值；步骤5、比较待预测可交联料在交联反应放热峰的热焓值与热焓标准值；交联料为交联剂和聚乙烯。

Description

一种交联聚乙烯电缆绝缘材料可靠性预测方法
本申请要求于2022年03月22日提交中国专利局、申请号为2022102837091、发明名称为“一种交联聚乙烯电缆绝缘材料可靠性预测方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请属于电缆技术领域，尤其涉及一种交联聚乙烯电缆绝缘材料可靠性预测方法。
背景技术
交联聚乙烯(XLPE)由于优异的电气性能使得交联聚乙烯绝缘材料作为长距离输电架空线的绝缘层绝缘材料、城市地下电缆的绝缘层绝缘材料被广泛应用。
交联聚乙烯的制备方法为利用交联剂分解产生的活性自由基将线性分子链连接为具有网状结构的、优异电气性能的交联聚乙烯绝缘材料，在交联剂作为可交联粒料投入制造交联聚乙烯电缆绝缘层之前，由于存储温度和存储时间等原因，交联剂会自发分解。如过氧化二异丙苯等交联剂需要在低温且暗光条件下保存，其分解半衰期随温度上升呈指数下降趋势。因此，在不同储存条件下的交联粒料会影响交联反应的交联度，而交联聚乙烯的负载下伸长率与其交联度密切相关，即在不同储存条件下的交联粒料制备得到的交联聚乙烯的负载下伸长率不同。
当使用负载下伸长率过高的交联聚乙烯作为电缆绝缘层绝缘材料时会导致电缆绝缘层不可靠，GB/T 18890.2-2015中关于热延伸实验部分规 定220kV电缆绝缘用XLPE材料的负载下伸长率不大于100％。目前，对交联聚乙烯电缆绝缘材料可靠性的评估方法需要对交联聚乙烯电缆绝缘材料进行热延伸等实验，缺乏预测方法。
发明内容
有鉴于此，本申请提供了一种交联聚乙烯电缆绝缘材料可靠性预测方法，通过计算可交联料的交联反应放热峰的热焓值，并利用该热焓值与聚乙烯电缆绝缘层材料的负载下伸长率的负相关关系，判断聚乙烯电缆绝缘材料负载下伸长率，从而快速预测交联聚乙烯电缆绝缘材料的可靠性，解决了现有技术中缺乏交联聚乙烯电缆绝缘材料可靠性预测方法的技术问题。
本申请第一方面提供了一种交联聚乙烯电缆绝缘材料可靠性预测方法，包括以下步骤：
步骤1、若干组可交联料进行交联反应，得到若干组交联聚乙烯和若干组可交联料的交联反应放热峰的热焓值；
步骤2、若干组交联聚乙烯进行热延伸实验，得到若干组交联聚乙烯负载下伸长率；
步骤3、基于若干组可交联料的交联反应放热峰的热焓值与若干组交联聚乙烯负载下伸长率建立交联聚乙烯电缆绝缘材料可靠性预测曲线；
步骤4、待预测可交联料进行交联反应，得到待预测可交联料在交联反应放热峰的热焓值；
步骤5、比较待预测可交联料在交联反应放热峰的热焓值与热焓标准值；
所述可交联料内含有交联剂和聚乙烯。
优选的，步骤5之后，还包括：
步骤6、待预测可交联料的交联反应放热峰的热焓值输入交联聚乙烯电缆绝缘材料可靠性预测曲线，得到待预测交联聚乙烯负载下伸长率；
步骤7、比较待预测交联聚乙烯负载下伸长率与标准值。
需要说明的是，本申请所述的标准值可以是GB/T 18890.2-2015中关于热延伸实验部分所规定的220kV电缆绝缘用XLPE材料的负载下伸长率标准值(＜100％)，也可以是自定义的或者其他国标中定义的标准值。而热焓标准值在本申请中为8.08655J/g。
优选的，所述交联聚乙烯电缆绝缘材料可靠性预测曲线为交联聚乙烯负载下伸长率预测曲线。
需要说明的是，交联聚乙烯负载下伸长率预测曲线的建立方法是以热焓值为横坐标，交联聚乙烯负载下伸长率为纵坐标建立的。
优选的，若干组可交联料进行交联反应，得到若干组交联聚乙烯和若干组可交联料的交联反应放热峰的热焓值包括：
若干组可交联料在差示扫描量热仪中进行交联反应，得到若干组交联聚乙烯和若干组可交联料的交联反应放热峰的热焓值。
优选的，所述得到若干组可交联料的交联反应放热峰的热焓值包括：通过差示扫描量热仪的热流-时间图像的积分区域得到若干组可交联料的交联反应放热峰的热焓值。
优选的，所述热流-时间图像的积分区域的计算方法为：以出现交联反应放热峰前的热流图像为基线，以基线与热流曲线的切点为积分上、下限。
优选的，所述交联剂为过氧化物。
优选的，所述过氧化物为过氧化二异丙苯(DCP)。
优选的，若干组可交联料在差示扫描量热仪中进行交联反应包括：
将5mg～10mg尺寸为0.5mm×0.5mm×0.5mm的若干组可交联料分别在差示扫描量热仪坩埚中进行交联反应。
优选的，若干组可交联料放入差示扫描量热仪中进行交联反应包括：用氮气吹扫差示扫描量热仪后，将5mg～10mg尺寸为0.5mm×0.5mm×0.5mm 的若干组可交联料分别在差示扫描量热仪专用坩埚中进行交联反应。
优选的，所述氮气的纯度大于99.999％。
综上所述，本申请提供了一种交联聚乙烯电缆绝缘材料可靠性预测方法，预测方法包括：先通过将若干组可交联料进行交联反应得到若干组交联聚乙烯和若干组可交联料的交联反应放热峰的热焓值，再建立交联聚乙烯电缆绝缘材料可靠性预测曲线，最后获取待预测可交联料的交联反应放热峰的热焓值并输入交联聚乙烯电缆绝缘材料可靠性预测曲线得到交联聚乙烯负载下伸长率；其中，在若干组可交联料进行交联反应过程中，可交联料粒料先剧烈吸热使聚乙烯树脂熔融的同时交联剂DCP逐渐分解，当温度进一步升高后，交联反应开始进行，热流曲线中出现相对微弱的交联反应放热峰，其强度与交联反应完成程度成正相关，因此可以通过计算不同可交联料在升温过程中交联反应放热峰的热焓值来评价其活性的强弱，而不同活性的可交联料会影响交联反应的交联度，而交联聚乙烯的负载下伸长率与其交联度密切相关，成正比关系，即交联粒料的活性越低，交联聚乙烯的负载下伸长率越大。因此，本申请通过计算交联剂在交联反应放热峰的热焓值，利用交联剂的热焓值与聚乙烯电缆绝缘材料负载下伸长率的负相关关系，判断聚乙烯电缆绝缘材料负载下伸长率，当负载下伸长率低于标准数值时，即判定用此交联聚乙烯制备的交联聚乙烯电缆绝缘材料不可靠，不用再次进行热延伸等实验，可以快速预测交联聚乙烯电缆绝缘材料的可靠性，解决了现有技术中缺乏交联聚乙烯电缆绝缘材料可靠性预测方法的技术问题。
附图说明
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍。显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来 讲，在不付出创造性劳动性的前提下，还可以根据这些附图获得其它的附图。
图1为本申请实施例3提供的一种交联聚乙烯电缆绝缘材料可靠性预测方法流程示意图；
图2为本申请实施例1提供的可交联料在交联反应放热峰的热焓值计算方法示意图；
图3为本申请实施例2建立交联聚乙烯电缆绝缘材料可靠性预测曲线示意图。
具体实施方式
本申请提供了一种交联聚乙烯电缆绝缘材料可靠性预测方法，通过可交联料的交联反应放热峰的热焓值，利用可交联料的热焓值与聚乙烯电缆绝缘材料负载下伸长率的联系，判断聚乙烯电缆绝缘材料负载下伸长率，从而快速预测交联聚乙烯电缆绝缘材料的可靠性，解决了现有技术中缺乏交联聚乙烯电缆绝缘材料可靠性预测方法的技术问题。
下面将对本申请实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其它实施例，都属于本申请保护的范围。
其中，以下实施例所用试剂或原料均为市售或自制。
实施例1
本实施例1提供了可交联料在交联反应放热峰的热焓值计算方法，包括以下步骤：
1.1、将若干组可交联粒料裁剪为0.5mm×0.5mm×0.5mm的碎屑，再将裁剪得到的碎屑置于DSC实验专用铝制坩埚中，每次DSC实验所需材料质量为5mg～10mg，放置碎屑时应保证其与坩埚底部接触良好，加盖坩埚 盖后压制封装，完成DSC实验所需试样制备；
1.2、将装有可交联料的坩埚和参比坩埚(空坩埚)置于DSC实验仪内样品架上，实验程序包括两次升温过程(通过第二次升温确认第一次实验效果)，两次升温过程中均从30℃升温至220℃，升温速率为10℃/min，测量升温过程中流过试样的热流及空坩埚的热流，最终得到流过可交联料本身的热流；
1.3、以DSC实验仪测得试样第一次升温时的热流数据绘制出热流-时间图像，用于交联反应放热焓的计算；
以出现交联反应放热峰前的热流图像为基线，以基线与热流曲线的切点为积分上、下限，积分封闭区域内的面积即可得到可交联料整个升温过程中的交联反应放热焓，如下说明书附图2内阴影部分所示；
其中，称量试样质量时应精确至0.01mg，且新粒料及存储后粒料的质量差应小于5％；同时DSC实验仪工作时需保证氮气(纯度≥99.999％)吹扫环境，以避免试样在升温熔融及降温结晶过程中发生氧化反应影响实验精度。若同一试样在第二次升温过程中由热流曲线计算出的交联反应放热焓大于0.1J/g，则说明该试样内的可交联料在第一次升温过程中交联不充分，需重新进行实验。
实施例2
本实施例2提供了基于交联料在交联反应放热峰的热焓值与交联料的负载下伸长率建立交联聚乙烯电缆绝缘材料可靠性预测曲线的实施例：
步骤1、将新粒料、存储一年、存储五年以及存储十年的220kV高压交联电缆绝缘层可交联料在差示扫描量热仪中进行交联反应，得到新粒料、存储一年、存储五年以及存储十年可交联料制得的交联聚乙烯和新粒料、存储一年、存储五年以及存储十年的可交联料的交联反应放热峰的热焓值，其中，交联料在交联反应放热峰的热焓值的计算参考实施例1，具体数值参见表1；
步骤2、将新粒料、存储一年、存储五年以及存储十年可交联料制得的交联聚乙烯按照国标GB/T 18890.2-2015进行热延伸实验，具体数值参见表2；
Figure PCTCN2022130863-appb-000001
表1
Figure PCTCN2022130863-appb-000002
表2
由表1-2可知，随着存储时间的延长，可交联料在DSC实验中测得的交联反应放热峰减弱，放热量也逐渐减小。当存储时间达到5年时，测得可交联料的交联反应放热焓下降约30％，这是由于在长期存储中，可交联料内DCP逐渐分解，可交联料活性下降，使得可交联料在升温至交联温度时交联反应进行不充分所致，同时，由表2中热延伸实验结果可知，随着存储时间的延长，可交联料在热延伸实验中测得的负载下伸长率逐渐增大，即通过将若干组交联料在差示扫描量热仪中进行交联反应中得到的热焓值即可 判断交联聚乙烯负载下伸长率，热焓值与交联聚乙烯负载下伸长成负相关关系，从而可以基于新粒料、存储一年、存储五年以及存储十年交联料在交联反应放热峰的热焓值与若干组交联聚乙烯负载下伸长率建立交联聚乙烯电缆绝缘材料可靠性预测曲线，依据已有实验数据可得图3所示可靠性预测曲线。由图3可知，交联聚乙烯负载下伸长率与热焓值应符合线性关系，通过曲线拟合便可得到负载下伸长率与热焓值的特征方程。图中水平虚线为负载下伸长率为100％标准线，其与图中拟合直线的交点为8.08655J/g。因此可以认为在本示例中，当待可交联料测得交联反应放热焓值大于8.08655J/g时，该可交联料的活性仍满足所需性能要求，由其制得的交联聚乙烯电缆绝缘材料的可靠性符合国标。
实施例3
本实施例3提供了一种交联聚乙烯电缆绝缘材料可靠性预测方法：包括以下步骤：
步骤1、新粒料、存储一年、存储五年以及存储十年可交联料进行交联反应，得到四组交联聚乙烯和可交联料的交联反应放热峰的热焓值，其中，交联料在交联反应放热峰的热焓值的计算参考实施例1，具体数值参见表1；
步骤2、新粒料、存储一年、存储五年以及存储十年交联聚乙烯进行热延伸实验，得到新粒料、存储一年、存储五年以及存储十年交联聚乙烯负载下伸长率，其中，负载下伸长率的具体数值参见表2。
步骤3、基于若干组可交联料的交联反应放热峰的热焓值与若干组交联聚乙烯负载下伸长率建立交联聚乙烯电缆绝缘材料可靠性预测曲线；其中，热焓值与交联聚乙烯负载下伸长率成负相关关系，从而可以基于新粒料、存储一年、存储五年以及存储十年可交联料在交联反应放热峰的热焓值与若干组交联聚乙烯负载下伸长率建立交联聚乙烯电缆绝缘材料可靠性预测曲线。
步骤4、待预测可交联料进行交联反应，得到待预测可交联料在交联反应放热峰的热焓值；其中，待预测可交联料为存储任意时间、任意温度或其他储存条件下的交联料。
步骤5、待预测可交联料的交联反应放热峰的热焓值输入交联聚乙烯电缆绝缘材料可靠性预测曲线，得到待预测交联聚乙烯负载下伸长率；
需要说明的是，在对交联粒料加热的过程中，升温至110℃前，粒料剧烈吸热使得DSC热流曲线中出现明显的吸热峰。在该阶段，可交联料内聚乙烯树脂熔融的同时交联剂DCP逐渐分解，当温度进一步升高后，交联反应开始进行，热流曲线中出现相对微弱的交联反应放热峰，其强度与交联反应完成程度成正相关。因此可以通过计算不同可交联料在升温过程中交联反应放热峰的热焓值来评价其交联度的强弱，进而预测XLPE材料的热延伸性能，与现有技术相比，本发明中提出采用DSC实验将可交联料的交联反应放热焓与制得XLPE材料的热延伸性能联系起来，灵活、快速地实现了对交联聚乙烯可靠性进行预测。
以上所述实施例的各技术特征可以进行任意的组合，为使描述简洁，未对上述实施例中的各个技术特征所有可能的组合都进行描述，然而，只要这些技术特征的组合不存在矛盾，都应当认为是本说明书记载的范围。
以上所述实施例仅表达了本申请的几种实施方式，其描述较为具体和详细，但并不能因此而理解为对发明专利范围的限制。应当指出的是，对于本领域的普通技术人员来说，在不脱离本申请构思的前提下，还可以做出若干变形和改进，这些都属于本申请的保护范围。因此，本申请专利的保护范围应以所附权利要求为准，说明书及附图可以用于解释权利要求的内容。

Claims (10)

  1. 一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，包括以下步骤：
    步骤1、若干组可交联料进行交联反应，得到若干组交联聚乙烯和若干组可交联料的交联反应放热峰的热焓值；
    步骤2、若干组交联聚乙烯进行热延伸实验，得到若干组交联聚乙烯负载下伸长率；
    步骤3、基于若干组可交联料的交联反应放热峰的热焓值与若干组交联聚乙烯负载下伸长率建立交联聚乙烯电缆绝缘材料可靠性预测曲线；
    步骤4、待预测可交联料进行交联反应，得到待预测可交联料在交联反应放热峰的热焓值；
    步骤5、比较待预测可交联料在交联反应放热峰的热焓值与热焓标准值；所述交联料为交联剂和聚乙烯。
  2. 根据权利要求1所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，步骤5之后，还包括：
    步骤6、待预测可交联料在交联反应放热峰的热焓值输入交联聚乙烯电缆绝缘材料可靠性预测曲线，得到待预测交联聚乙烯负载下伸长率；
    步骤7、比较待预测交联聚乙烯负载下伸长率与标准值。
  3. 根据权利要求1～2中任一项所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，所述若干组可交联料进行交联反应，得到若干组交联聚乙烯和若干组可交联料在交联反应放热峰的热焓值包括：
    若干组交联料在差示扫描量热仪中进行交联反应，得到若干组交联聚乙烯和若干组可交联料的交联反应放热峰的热焓值。
  4. 根据权利要求3所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，所述得到若干组可交联料的交联反应放热峰的热焓值包括：通过差示扫描量热仪的热流-时间图像的积分区域得到若干组交联料在交联反应放 热峰的热焓值。
  5. 根据权利要求4所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，所述热流-时间图像的积分区域的确认方法为：以出现交联反应放热峰前的热流图像为基线，以基线与热流曲线的切点为积分上、下限。
  6. 根据权利要求1～5中任一项所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，所述交联剂为过氧化物。
  7. 根据权利要求6所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，所述过氧化物为过氧化二异丙苯。
  8. 根据权利要求3所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，所述若干组可交联料在差示扫描量热仪中进行交联反应包括：将5mg～10mg尺寸为0.5mm×0.5mm×0.5mm的若干组可交联料分别放入差示扫描量热仪的坩埚中进行交联反应。
  9. 根据权利要求8所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，若干组可交联料放入差示扫描量热仪中进行交联反应包括：用氮气吹扫差示扫描量热仪后，将5mg～10mg尺寸为0.5mm×0.5mm×0.5mm的若干组可交联料分别放入差示扫描量热仪坩埚中进行交联反应。
  10. 根据权利要求9所述的一种交联聚乙烯电缆绝缘材料可靠性预测方法，其特征在于，所述氮气的纯度大于99.999％。
PCT/CN2022/130863 2022-03-22 2022-11-09 一种交联聚乙烯电缆绝缘材料可靠性预测方法 WO2023179043A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202210283709.1 2022-03-22
CN202210283709.1A CN114660117A (zh) 2022-03-22 2022-03-22 一种交联聚乙烯电缆绝缘材料可靠性预测方法

Publications (1)

Publication Number Publication Date
WO2023179043A1 true WO2023179043A1 (zh) 2023-09-28

Family

ID=82030495

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/130863 WO2023179043A1 (zh) 2022-03-22 2022-11-09 一种交联聚乙烯电缆绝缘材料可靠性预测方法

Country Status (2)

Country Link
CN (1) CN114660117A (zh)
WO (1) WO2023179043A1 (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114660117A (zh) * 2022-03-22 2022-06-24 南方电网科学研究院有限责任公司 一种交联聚乙烯电缆绝缘材料可靠性预测方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105300829A (zh) * 2015-11-24 2016-02-03 国网江西省电力科学研究院 一种快速检测交联聚乙烯电缆绝缘质量性能的方法
EP3553493A1 (en) * 2018-04-11 2019-10-16 Crosslink Finland Oy A method and a system for determining a crosslinking degree of a crosslinked polymer pipe
CN110579692A (zh) * 2019-09-17 2019-12-17 国网四川省电力公司电力科学研究院 一种现场快速测量xlpe电缆交联度的方法
CN111060472A (zh) * 2019-12-23 2020-04-24 重庆大学 一种表征分析交联聚乙烯海缆绝缘材料老化状态的方法
CN114660117A (zh) * 2022-03-22 2022-06-24 南方电网科学研究院有限责任公司 一种交联聚乙烯电缆绝缘材料可靠性预测方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105300829A (zh) * 2015-11-24 2016-02-03 国网江西省电力科学研究院 一种快速检测交联聚乙烯电缆绝缘质量性能的方法
EP3553493A1 (en) * 2018-04-11 2019-10-16 Crosslink Finland Oy A method and a system for determining a crosslinking degree of a crosslinked polymer pipe
CN110579692A (zh) * 2019-09-17 2019-12-17 国网四川省电力公司电力科学研究院 一种现场快速测量xlpe电缆交联度的方法
CN111060472A (zh) * 2019-12-23 2020-04-24 重庆大学 一种表征分析交联聚乙烯海缆绝缘材料老化状态的方法
CN114660117A (zh) * 2022-03-22 2022-06-24 南方电网科学研究院有限责任公司 一种交联聚乙烯电缆绝缘材料可靠性预测方法

Also Published As

Publication number Publication date
CN114660117A (zh) 2022-06-24

Similar Documents

Publication Publication Date Title
WO2023179043A1 (zh) 一种交联聚乙烯电缆绝缘材料可靠性预测方法
EP2414451B1 (en) Cable with high level of breakdown strength after ageing
US10844209B2 (en) Process for making crosslinked cable insulation using high melt strength ethylene-based polymer made in a tubular reactor and optionally modified with a branching agent
BR112012023424B1 (pt) Cabo de alimentação cc, seu processo de produção e uso de uma composição de polímero
CN103483662B (zh) 一种交联聚乙烯电缆绝缘材料
BRPI0714147A2 (pt) polipropileno com ramificaÇÕes de cadeia curta
CN107868328B (zh) 一种硅烷交联型半导电屏蔽材料及其制备方法和应用
BRPI0714425A2 (pt) filme de isolamento elÉtrico
CN102183539B (zh) 一种快速检测交联聚乙烯电缆绝缘料结构的方法
CN103314049A (zh) 具有改进击穿强度的可回收热塑性绝缘体
EP3278158B1 (en) Flooding compounds for telecommunication cables
US10679769B2 (en) Cable with improved electrical properties
CN109912881A (zh) 包含异种橡胶成分的用于包覆电缆的聚烯烃树脂组合物
Gerelt-Od et al. In situ Raman investigation of resting thermal effects on gas emission in charged commercial 18650 lithium ion batteries
US20190326033A1 (en) Cable with advantageous electrical properties
BR112020019049B1 (pt) Material compósito semicondutor, método para produção do material compósito semicondutor, produto de polietileno reticulado, artigo fabricado, dispositivo condutor elétrico, método para a condução de eletricidade e material compósito semicondutor termicamente ciclado
BR112020019011A2 (pt) Compósito de copolímero orgânico polar e negro de fumo de molhabilidade ultrabaixa
BR112020019372A2 (pt) Compósito de polímero orgânico não polar e negro de fumo de molhabilidade ultrabaixa
CN106009236A (zh) 二步法制备10kV及以下电线电缆用硅烷交联聚乙烯绝缘材料的方法
CN109651719A (zh) 一种核反应堆中压电缆用可剥离绝缘屏蔽料及其制备方法
JP4694225B2 (ja) 同軸ケーブルの吸水量を低減する方法及び同軸ケーブルのｔａｎδを低減する方法
CN106009224A (zh) 一步法制备10kV及以下黑色电线电缆用硅烷交联聚乙烯绝缘材料的方法
CN104678086A (zh) 快速鉴别聚乙烯护套材料是否使用回收废旧塑料的方法
CN109651720A (zh) 一种核反应堆中压电缆用导体屏蔽料及其制备方法
Stevens et al. Thermoplastic blend balanced property developments for sustainable high performance power cables

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22933094

Country of ref document: EP

Kind code of ref document: A1